Merge pull request #1708 from chenglou/displayName

Use double quote for transformed `displayName`
Merge pull request #2452 from Shahor/master

Trailing commas break old IE versions
Merge pull request #2482 from BinaryMuse/bkt/fix-stroke-opacity

Add strokeOpacity to unitless CSS properties
Merge pull request #2489 from cody/form

Add Attributes formAction, formEncType, formMethod and formTarget
Merge pull request #2610 from zpao/update-commonjs-example

Update commonjs example for 0.12
Merge pull request #2658 from ianobermiller/margin-attrs

Support marginHeight and marginWidth attributes
Merge pull request #2726 from zpao/createElement-undefined-null

Protect better against createElement(null/undefined)
Conflicts:
	src/classic/element/__tests__/ReactElementValidator-test.js
update docs for 0.12.2 changes
Readme + Changelog for 0.12.2
v0.12.2 blog post
Bump version for 0.12.2
0.12.2 starter kit