Convert README.rst to README.md (conda#11544)

* Convert README to markdown
* Convert remaining RST file to MD

Co-authored-by: Jannis Leidel <[email protected]>
Co-authored-by: Katherine Kinnaman <[email protected]>

MANIFEST.in

@@ -1,6 +1,6 @@
 include CHANGELOG.md
 include LICENSE.txt
 include MANIFEST.in
-include README.rst
+include README.md
 include setup.cfg
 include setup.py

README.md

@@ -0,0 +1,138 @@
+[conda-logo]: https://s3.amazonaws.com/conda-dev/conda_logo.svg
+[ci-tests-badge]: https://github.com/conda/conda/actions/workflows/ci.yml/badge.svg
+[ci-images-badge]: https://github.com/conda/conda/actions/workflows/ci-images.yml/badge.svg
+[codecov-badge]: https://img.shields.io/codecov/c/github/conda/conda/master.svg?label=coverage
+[release-badge]: https://img.shields.io/github/release/conda/conda.svg
+[gitpod]: https://gitpod.io/button/open-in-gitpod.svg
+
+[![Conda Logo][conda-logo]](https://github.com/conda/conda)
+
+
+[![CI Tests (GitHub Actions)][ci-tests-badge]](https://github.com/conda/conda/actions/workflows/ci.yml)
+[![CI Images (GitHub Actions)][ci-images-badge]](https://github.com/conda/conda/actions/workflows/ci-images.yml)
+[![Codecov Status][codecov-badge]](https://codecov.io/gh/conda/conda/branch/master)
+[![latest release version][release-badge]](https://github.com/conda/conda/releases)
+
+Conda is a cross-platform, language-agnostic binary package manager. It is the
+package manager used by [Anaconda](https://www.anaconda.com/distribution/) installations, but it may be
+used for other systems as well. Conda makes environments first-class
+citizens, making it easy to create independent environments even for C
+libraries. Conda is written entirely in Python, and is BSD licensed open
+source.
+
+Conda is enhanced by organizations, tools, and repositories created and managed by
+the amazing members of the conda community. Some of them can be found
+[here](https://github.com/conda/conda/wiki/Conda-Community).
+
+
+## Installation
+
+Conda is a part of the [Anaconda Distribution](https://repo.anaconda.com).
+Use [Miniconda](https://docs.conda.io/en/latest/miniconda.html) to bootstrap a minimal installation
+that only includes conda and its dependencies.
+
+
+## Getting Started
+
+If you install the Anaconda Distribution, you will already have hundreds of packages
+installed. You can see what packages are installed by running
+
+```bash
+$ conda list
+```
+
+to see all the packages that are available, use
+
+```bash
+$ conda search
+```
+
+and to install a package, use
+
+```bash
+$ conda install <package-name>
+```
+
+The real power of conda comes from its ability to manage environments.
+In conda, an environment can be thought of as a completely separate installation.
+Conda installs packages into environments efficiently using [hard links](https://en.wikipedia.org/wiki/Hard_link) by default when it is possible, so
+environments are space efficient, and take seconds to create.
+
+The default environment, which `conda` itself is installed into is called
+`base`. To create another environment, use the `conda create`
+command. For instance, to create an environment with the IPython notebook and
+NumPy 1.6, which is older than the version that comes with Anaconda by
+default, you would run:
+
+```bash
+$ conda create -n numpy16 ipython-notebook numpy=1.6
+```
+
+This creates an environment called `numpy16` with the latest version of
+the IPython notebook, NumPy 1.6, and their dependencies.
+
+We can now activate this environment, use
+
+```bash
+$ conda activate numpy16
+```
+
+This puts the bin directory of the `numpy16` environment in the front of the
+`PATH`, and sets it as the default environment for all subsequent conda commands.
+
+To go back to the base environment, use
+
+```bash
+$ conda deactivate
+```
+
+## Building Your Own Packages
+
+You can easily build your own packages for conda, and upload them
+to [anaconda.org](https://anaconda.org), a free service for hosting
+packages for conda, as well as other package managers.
+To build a package, create a recipe. Package building documentation is available
+[here](https://docs.conda.io/projects/conda-build/en/latest/).
+See [AnacondaRecipes](https://github.com/AnacondaRecipes) for the recipes that make up the Anaconda Distribution and `defaults` channel.
+[Conda-forge](https://conda-forge.org/feedstocks/) and [Bioconda](https://github.com/bioconda/bioconda-recipes) are community-driven conda-based distributions.
+
+To upload to anaconda.org, create an account. Then, install the
+anaconda-client and login
+
+```bash
+$ conda install anaconda-client
+$ anaconda login
+```
+
+Then, after you build your recipe
+
+```bash
+$ conda build <recipe-dir>
+```
+
+you will be prompted to upload to anaconda.org.
+
+To add your anaconda.org channel, or other's channels, to conda so
+that `conda install` will find and install their packages, run
+
+```bash
+$ conda config --add channels https://conda.anaconda.org/username
+```
+
+(replacing `username` with the username of the person whose channel you want
+to add).
+
+## Getting Help
+
+- [Documentation](https://docs.conda.io/projects/conda/en/latest)
+- [Twitter](https://twitter.com/condaproject)
+- [Slack](https://conda.slack.com)
+- [Bug Reports/Feature Requests](https://github.com/conda/conda/issues)
+- [Installer/Package Issues](https://github.com/ContinuumIO/anaconda-issues/issues)
+
+## Contributing
+
+[![open in gitpod for one-click development][gitpod]](https://gitpod.io/#https://github.com/conda/conda)
+
+Contributions to conda are welcome. See the [contributing](CONTRIBUTING.md) documentation
+for instructions on setting up a development environment.

conda/_vendor/README.rst → conda/_vendor/README.md

@@ -1,8 +1,7 @@
-conda._vendor
--------------
+## `conda._vendor`
 
 Conda's pure-python dependencies will be
-`vendored <http://stackoverflow.com/questions/26217488/what-is-vendoring>`_
+[vendored](http://stackoverflow.com/questions/26217488/what-is-vendoring)
 until conda 5.0 when conda will be isolated in its own private environment.
 
 Introduction of dependencies for the 4.x series is discussed in

conda/base/README.md

@@ -0,0 +1,18 @@
+## `conda.base`
+
+Code in `conda.base` is the lowest level of the application stack. It is loaded and executed
+virtually every time the application is executed. Any code within, and any of its imports, must
+be highly performant.
+
+Conda modules importable from `conda.base` are:
+
+- `conda._vendor`
+- `conda.base`
+- `conda.common`
+
+Modules prohibited from importing `conda.base` are:
+
+- `conda._vendor`
+- `conda.common`
+
+All other `conda` modules may import from `conda.base`.

conda/common/README.md

@@ -0,0 +1,9 @@
+## `conda.common`
+
+Code in `conda.common` is not conda-specific. Technically, it sits **aside** the application
+stack and not **within** the stack. It is able to stand independently on its own.
+The **only** allowed imports of conda code in `conda.common` modules are imports of other
+`conda.common` modules and imports from `conda._vendor`.
+
+If objects are needed from other parts of conda, they should be passed directly as arguments to
+functions and methods.

conda/core/README.md

@@ -0,0 +1,21 @@
+## `conda.core`
+
+Code in `conda.core` is the core logic. It is strictly forbidden from having side effects.
+No printing to stdout or stderr, no disk manipulation, no http requests.
+All side effects should be implemented through `conda.gateways`. Objects defined in
+`conda.models` should be heavily preferred for `conda.core` function/method arguments
+and return values.
+
+Conda modules importable from `conda.core` are:
+
+- `conda._vendor`
+- `conda.common`
+- `conda.core`
+- `conda.models`
+- `conda.gateways`
+
+Conda modules strictly off limits for import within `conda.core` are:
+
+- `conda.api`
+- `conda.cli`
+- `conda.client`