Create CONVENTIONS.md

First draft of a document to assist new cookbook developers.
Improves customization of dock preferences

- namespaces preferences under 'sprout'
- adjusts multi-word attribute names to use underscores
- makes more of the attributes optional
- comments out some attributes to allow more of the default settings to be used.  But I left the comments in so that people would have a better idea of what could be done.
Merge pull request #196 from codeword/dockPreferences

Improves customization of dock preferences
qt works without --HEAD on Mavericks now
(it actually doesn't work with --HEAD anymore)
Merge pull request #200 from hungryzi/qt

qt works without --HEAD on Mavericks now
Merge pull request #192 from mikem/fix-home-dir-in-sidebar

Fix adding home dir to Finder sidebar
Update alfred recipe

Alfred is no longer distributed as .dmg but instead as a zip file.
pivotal_workstation is osx only, remove non-osx branches
Avoid anti-pattern of checking platform in osx-only cookbooks
Update homebrew repo URL
Merge pull request #221 from ryanhanks/update_homebrew_repo_url

Update homebrew repo URL
Merge branch 'master' into update-alfred-recipe
Use Homebrew Cask for Alfred
Merge branch 'update-alfred-recipe' into mike-customizations

Conflicts:
	sprout-osx-apps/recipes/alfred.rb
	sprout-osx-settings/attributes/dock_preferences.rb