Fix npm react having wrong version dependency for envify
Don't get selection if no active element

Fixes #694.

Previously, it could be that there was an active element that was removed in between mousedown and mouseup.
Further cleanup of isEventSupported
Fix WheelEvent incorrectly inverting sign of deltaY
Don't mutate passed-in props, take 2
Use proper window object for iframe in enter/leave

Fixes #788.
Add display name in more cases
Merge pull request #799 from spicyj/display-name

Add display name in more cases
Don't set max_line_length for *.md
Warn for common forms misuse
Revert textContent

Reverts 309a88bcf62c1c64a2b91c0eb753c19209a425b2 because this is causing
issues internally. I'll try to get a repro soon.
Fix URL in displayName description
Merge pull request #844 from xixixao/patch-1

Fix URL in displayName description
Don't use the min build in getting started guide
Remove two more react.min.js references
Merge pull request #846 from spicyj/docs-nomin

Remove two more react.min.js references
Don't tack on EventPluginHub globally
Merge pull request #757 from spicyj/ng

Don't tack on EventPluginHub globally
Merge pull request #718 from syranide/npmenvify

Fix npm react having wrong version dependency for envify
Fix potential memory leak when unmounting

Fixes #781.