Merge pull request #1 from google/master

Merge google/iosched master
Remove mention of lpreview from BUILDING.md

Removed lpreview build section
Updated gradle commands (removed lpreview and classic productFlavors)
Updated SDK Manager packages needed (removed kiktkat, included lollipop)

SDK Build-tools version 21 has solved and unsolved issues, Current rev is 21.0.1
https://code.google.com/p/android/issues/detail?id=77629
http://stackoverflow.com/questions/26446610/android-gradle-project-upgrading-build-tools-to-21-0-1-aapt-throws-exception
Merge pull request #60 from ardock/update-building

Remove mention of lpreview from BUILDING.md (and update build instructions)
Merge pull request #62 from romannurik/master

Fix ScrimInsets* classes to use ViewCompat.postInvalidateOnAnimation
Fix for 20.0.0 build tools bug

reference: https://code.google.com/p/android/issues/detail?id=77629
Merge pull request #65 from VipSaran/master

Fix for 20.0.0 build tools bug