Add Attributes formAction, formEncType, formMethod and formTarget

This resolves #2425.
Fix typo in comment of jquery-bootstrap example
Support marginHeight and marginWidth attributes

marginHeight and marginWidth are used on iframes to set the default body margin inside the iframe.
Don't need MUST_USE_ATTRIBUTE for margin(Width|Height)
Merge pull request #2489 from cody/form

Add Attributes formAction, formEncType, formMethod and formTarget
Merge pull request #2658 from ianobermiller/margin-attrs

Support marginHeight and marginWidth attributes
Update 10.6-update.md

Spelling fix.
Merge pull request #2671 from benkeen/patch-1

Update 10.6-update.md
The same problem in issue #2648
Merge pull request #2672 from cookfront/master

The same problem in issue #2648
Merge branch 'master' into rnbwd
Fix new lint errors

We'll get to lint parity soon and then not need to do this.
Merge pull request #2677 from zpao/lint-internal

Fix new lint errors
Add missing verb

This adds a missing verb in JSX-in-depth doc.
Merge pull request #2679 from tschaub/patch-1

Add missing verb in docs
Add Chinese translation of jsx-in-depth
Combine BeforeInput and Composition event plugins

In order to improve support for Chinese and Japanese IME input in
Internet Explorer, use a fallback composition state to determine
inserted text. IE composition events are mostly okay, except for
certain punctuation characters that are ignored. Using the fallback, we
can detect these characters.

The fallback is also useful for emitting `beforeInput` events, so it
makes sense to simply combine these plugins.

This change also incorporates a recent change to the Google Input Tools
browser extension that exposes a `data` field via the `detail` object
on the custom composition events it emits.
Update BeforeInputEventPlugin.js
Merge pull request #2689 from camsong/master

Add Chinese translation of jsx-in-depth
Fixed ReactTestUtils scry for TextComponents.  Fixes issue #2654.