chore(build): various fixes to the changelog task

@ajoslin I've tested the changelog task locally and bumped into several issues for which I would like to push fixes:
* dependencies
  * there was a depndency missing on a changelog task
  * ngdoc was pointing to a git endpoint instead of a released version
* template
  * various fixes (mostly new lines) so it looks like the current / AngularJS one
  * sorting by a directive name in each section (feature, fix etc.)
* sha1 links are broken
  * missing config option
  * there is a bug in the changelog task, submitted PR: https://github.com/btford/grunt-conventional-changelog/pull/12