add label explore prototype
Revert changes to burndown.js #37
Update milestone view for consistency. #37
Add Label model and Labels collection. #37
Add the ability to filter on labels to the milestone view. #37
Merge remote-tracking branch 'origin/master' into stone-cold-tags

Conflicts:
	app/assets/javascripts/burndown.js
Fix merge commit mistake. #37
fixing days open legend position
add href to label links so they style as links
dont allow labels over issue list
Update label filtering selection and display logic. #37
Quick hack to get issue lists to display correct number. #37

This is only a temporary fix and will take more work to implement correctly
(I'm thinking with nested views) in the future.
Merge pull request #37 from appneta/stone-cold-tags

add label explore prototype