Add support for <dialog> tag.

fixes #2017
Throw an error when functions on `statics` clash due to duplicate keys
Throw if a reserved property is defined in 'statics'
Deprecate 'return false' in event handlers
Re-add  with warning and monitorCodeUse
Fixed style and comment nits
Test for both true and false
More info in monitorCodeUse call
Look on __reactBoundContext for displayName
Add 2048-react to open-source demos

Nothing too complicated, but I think it could be a fun beginner demo.
Indentation for eventHandlerName
Removed monitorCodeUse call
[docs] Update Flux TodoMVC Tutorial
[docs] fix nits
[docs] remove redundant paragraph
Use warning module
Docs: renamed input's state to `message`

Readers might feel confused with the actual input's `value` attribute.
Merge pull request #2036 from crm416/static-functions

Throw an error when functions on `statics` clash due to duplicate keys
Merge pull request #2039 from crm416/return-false

Deprecate 'return false' in event handlers
Fix typo