style(): Remove 'latedef' option from .jshintrc
chore(): Add .gitignore
feat(log): Add breaking changes section

* Follows [Commit Message Conventions](http://goo.gl/9lPYd) from
 AngularJS for breaking changes.
feat(log): Add smart 'github' option for commit links

* Uses a github repository, if found, to link to commits in the
 changelog
* If no github option is specified, tries to read the homepage from the
 'repository' or 'homepage' field of grunt.config('pkg')