load correct stylesheet
load vao extension
Update README.md

Add quick and easy advice on adding Mapbox GL as a CocoaPod
minor formatting tweaks
Merge pull request #65 from mapbox/readme-updates

README updates (closes #64)
Merge remote-tracking branch 'origin/load-extensions'
Remove canRotate check

Refs https://github.com/mapbox/mapbox-gl-native/issues/458
comment source code sections
abstract out common animation duration
be explicit about expected north reset duration
split out animated/non north reset
minor formatting & animation tweaks
fixes #66: add rotation constraints
 * check at completion of various interaction points
 * constrain rotation within limits when not complex gestures
 * bounce back to north for low zooms
 * various memory fixes
 * added delayed UI action utility
more Apple-like & convenient method
disregard quick zoom during rotation constraints & tweak behavior
fix up style APIs
tidy up iOS sample app & add style picker
fixes #67: gesture tweaks