workflow: improve git hooks setup

Author: yyx990803

.github/COMMIT_CONVENTION.md

@@ -2,6 +2,14 @@
 
 > This is adapted from [Angular's commit convention](https://github.com/conventional-changelog/conventional-changelog/blob/master/packages/conventional-changelog-angular/convention.md).
 
+#### TL;DR:
+
+Messages must be matched by the following regex:
+
+``` js
+/^(revert: )?(feat|fix|docs|style|refactor|perf|test|workflow|ci|chore|types)(\(.+\))?: .{1,50}/
+```
+
 #### Examples
 
 Appears under "Features" header, `compiler` subheader:

.github/CONTRIBUTING.md

@@ -40,18 +40,12 @@ You will need [Node.js](http://nodejs.org) **version 6+** and [Java Runtime Envi
 After cloning the repo, run:
 
 ``` bash
-$ npm install
-& npm run setup
+$ npm install # or yarn
 ```
 
-The `setup` script links two git hooks:
-
-- `pre-commit`: runs ESLint on staged files.
-- `commit-msg`: validates commit message format (see below).
-
 ### Committing Changes
 
-Commit messages should follow the [commit message convention](./COMMIT_CONVENTION.md) so that changelogs can be automatically generated. If git hooks have been properly linked, commit messages will be automatically validated upon commit. It is recommended to use `npm run commit` instead of `git commit`, which provides an interactive CLI for generating proper commit messages.
+Commit messages should follow the [commit message convention](./COMMIT_CONVENTION.md) so that changelogs can be automatically generated. Commit messages will be automatically validated upon commit. If you are not familiar with the commit message convention, you can use `npm run commit` instead of `git commit`, which provides an interactive CLI for generating proper commit messages.
 
 ### Commonly used NPM scripts