docs(CONTRIBUTING.md): add commitizen instructions

Author: stephensauceda

CONTRIBUTING.md

@@ -187,6 +187,8 @@ We have very precise rules over how our git commit messages can be formatted.  T
 readable messages** that are easy to follow when looking through the **project history**.  But also,
 we use the git commit messages to **generate the AngularJS change log**.
 
+The commit message formatting can be added using a typical git workflow or through the use of a CLI wizard ([Commitizen](https://github.com/commitizen/cz-cli)). To use the wizard, run `npm run commit` in your terminal after staging your changes in git.
+
 ### Commit Message Format
 Each commit message consists of a **header**, a **body** and a **footer**.  The header has a special
 format that includes a **type**, a **scope** and a **subject**: