Temp incompatible release

Support for installing custom Bazel version

Custom remote

build.sh: Remove old binaries before building new ones.

Fix bazelbuild#61: Do not execute tools/bazel when BAZELISK_SKIP_WRAP…

…PER is set. (bazelbuild#67)

* Fix bazelbuild#61: Do not execute tools/bazel when BAZELISK_SKIP_WRAPPER is set.

Bazelisk will set this environment variable when executing Bazel (or
a wrapper found in <workspace_root>/tools/bazel). This prevents Bazelisk
from executing itself in an infinite loop, in case the wrapper is
Bazelisk or somehow executes Bazelisk.

If you're using a wrapper in <workspace_root>/tools/bazel that downloads
Bazelisk and delegates to it, please set the BAZELISK_SKIP_WRAPPER
environment variable to ensure that Bazelisk directly executes Bazel.

* Skip wrapper delegation tests on Windows

Add support for GitHub auth token (bazelbuild#62)

This adds support for BAZELISK_GITHUB_TOKEN which is a GitHub token used
for API requests when it is set. This fixes the issue of being on a
shared network and getting rate limited when using bazelisk.

Fixes bazelbuild#18

Fixed searching of workspace on Windows. (bazelbuild#56)

Support last_downstream_green Bazel binary. (bazelbuild#45)

* Support last_downstream_green Bazel binary.

This commit modifies both Bazelisk implementations to support the
"last_downstream_green" version identifier, which refers to a Bazel
binary built at the most recent commit that passed the downstream
pipeline on CI (https://buildkite.com/bazel/bazel-at-head-plus-downstream).

Part of bazelbuild/continuous-integration#583.

* Fix wrong handling of slashes.

* Slash fix, part 2.

* Add test for last_downstream_green

Get up to 100 flags (instead of 30). (bazelbuild#41)

Instead of hard-coding the limit, we could also make multiple requests,
one for each page (https://developer.github.com/v3/#pagination).

But we don't expect the number of flags to grow indefinitely, so a limit
should work.

Fix error code and argument order (bazelbuild#36)

* Fix error code and argument order

- Exit with error code 1 if the build fails
- Fix a bug in a print message
- Insert arguments before "--" if any (otherwise, put them at the end)

* Update exit code