feat: Added validation commit msg file

Installation:
 * `cd <famous-angular-repo>`
 * `ln -s ../../validate-commit-msg.js .git/hooks/commit-msg`
feat: Added the changelog and release gulp tasks

Usage: `gulp changelog` and `gulp release`
The release task includes the changelog task.

Fixes #62
docs: updated the contribute section to include the commits validation
docs: updated the list of accepted types in the commit messages
Merge pull request #63 from ocombe/auto-changelog

feat: changelog / release tasks