docs: Update CONTRIBUTING.md (#242)

CONTRIBUTING.md

@@ -9,12 +9,15 @@ Make sure you have NodeJS 0.10 or higher and npm installed.
 1. Fork this repository and clone your fork
 1. Install dependencies: `npm install`
 1. Run a development server: `npm start`
+1. Navigate to [`http://localhost:9999/`][local] for a local test player
 
 ### Making Changes
 
 Refer to the [video.js plugin standards][standards] for more detail on best practices and tooling for video.js plugin authorship.
 
-When you've made your changes, push your commit(s) to your fork and issue a pull request against the original repository.
+Be sure to run `npm run lint -- --errors` prior to opening a pull request. This may output a bunch of warnings, but errors will result in a non-0 exit status which will be clearly presented to you with a line similar to `npm ERR! Exit status 1`
+
+When you've made your changes, push your commit(s) to your fork and issue a pull request against the original repository. The pull request template will include a checklist of things you may need to do before merging your changes.
 
 ### Running Tests
 
@@ -24,7 +27,6 @@ Testing is a crucial part of any software project. For all but the most trivial
 - In a specific browser: `npm run test:chrome`, `npm run test:firefox`, etc.
 - While development server is running (`npm start`), navigate to [`http://localhost:9999/test/`][local]
 
-
 [karma]: http://karma-runner.github.io/
 [local]: http://localhost:9999/test/
 [standards]: https://github.com/videojs/generator-videojs-plugin/blob/master/docs/standards.md