Introduce sprout-osx-git & sprout-osx-git::authors

* To manage ~/.git-authors as expected by git-duet
* This cookbook can house all git related recipes
Merge pull request #67 from pivotal-sprout/add-git-authors

Introduce sprout-osx-git & sprout-osx-git::authors
Add recipe for cdrtools

* provides `mkisofs`
  * http://cdrecord.berlios.de/private/cdrecord.html
Merge pull request #80 from aramprice/master

Add recipe for cdrtools