Update/lint README & CONTRIBUTING (RobotWebTools#420)

* Update/lint CONTRIBUTING

* Lint README

CONTRIBUTING.md

@@ -1,24 +1,23 @@
-roslibjs Build Setup
-====================
+# roslibjs Build Setup
 
 [Grunt](http://gruntjs.com/) is used for building, including concatenating, minimizing, documenting, linting, and testing.
 
-### Install Grunt and its Dependencies
+## Install Grunt and its Dependencies
 
  1. Install [Node.js](http://nodejs.org/) for your environment
  2. Install the build task runner, [Grunt](http://gruntjs.com/)
 
- 	```sh
-	$ [sudo] npm install -g grunt
- 	```
+```bash
+$ [sudo] npm install -g grunt
+```
  3. Install the dependencies and build dependencies
 
-	```sh
-	$ cd /path/to/roslibjs/
-   	$ [sudo] npm install
-	```
+```bash
+$ cd /path/to/roslibjs/
+$ [sudo] npm install
+```
 
-### Build with Grunt
+## Build with Grunt
 
 Before proceeding, please confirm you have installed the dependencies above.
 

README.md

@@ -2,45 +2,56 @@
 
 [![CI](https://github.com/RobotWebTools/roslibjs/actions/workflows/main.yml/badge.svg)](https://github.com/RobotWebTools/roslibjs/actions/workflows/main.yml)
 
-#### The Standard ROS JavaScript Library
+## The Standard ROS JavaScript Library
+
 For full documentation, see [the ROS wiki](http://wiki.ros.org/roslibjs) or check out some [working demos](http://robotwebtools.org/demos.html).
 
 [JSDoc](http://robotwebtools.org/jsdoc/roslibjs/current/) can be found on the Robot Web Tools website.
 
 This project is released as part of the [Robot Web Tools](http://robotwebtools.org/) effort.
 
-### Usage
+## Usage
+
 Pre-built files can be found in either [roslib.js](build/roslib.js) or [roslib.min.js](build/roslib.min.js).
 
 Alternatively, you can use the current release via the Robot Web Tools CDN: ([full](https://static.robotwebtools.org/roslibjs/current/roslib.js)) | ([min](https://static.robotwebtools.org/roslibjs/current/roslib.min.js))
 
-### Troubleshooting
+## Troubleshooting
 
 1. Check that connection is established. You can listen to error and
    connection events to report them to console. See
    examples/simple.html for a complete example:
 
-    ros.on('error', function(error) { console.log( error ); });
-    ros.on('connection', function() { console.log('Connection made!'); });
+   ```js
+   ros.on('error', function(error) { console.log( error ); });
+   ros.on('connection', function() { console.log('Connection made!'); });
+   ```
 
-1. Check that you have the websocket server is running on
+2. Check that you have the websocket server is running on
    port 9090. Something like this should do:
 
-    netstat -a | grep 9090
+   ```bash
+   netstat -a | grep 9090
+   ```
 
-### Dependencies
+## Dependencies
 
 roslibjs has a number of dependencies. You will need to run:
 
-`npm install`
+```bash
+npm install
+```
 
 Depending on your build environment.
 
-### Build
+## Build
+
 Checkout [CONTRIBUTING.md](CONTRIBUTING.md) for details on building.
 
-### License
+## License
+
 roslibjs is released with a BSD license. For full terms and conditions, see the [LICENSE](LICENSE) file.
 
-### Authors
+## Authors
+
 See the [AUTHORS.md](AUTHORS.md) file for a full list of contributors.