Don't escape slash; it's unnecessary

Fixes #1444.

Test Plan: grunt fasttest
Clarify when getDefaultProps is called

Fixes #1778.
Fix spelling/grammar in test comment
Fixing grunt jsx task in Windows

Spawning node directly instead of relying on shebang in the jsx-internal script

Fixes #1292
Merge pull request #1779 from spicyj/spell-gram

Fix spelling/grammar in test comment
Merge pull request #1780 from jbrantly/issue-1292

Fixing grunt jsx task in Windows
Update npm dependencies [skip ci]
Merge pull request #1461 from spicyj/no-esc-slash

Don't escape slash; it's unnecessary
make invariant show formatted actual errors in all unminified environments

Because we can have !__DEV__ but unminified, we still want to see the
message in those cases.
Give useful error when using two copies of React

If we don't error here, we end up with a confusing error later on in this.getDOMNode() where ReactMount doesn't have the proper container registered in its object.
Merge pull request #1531 from spicyj/two-face

Give useful error when using two copies of React
Add the built source to npm package. See #1699
Custom readme for react-tools

Of course this means I can no longer just npm publish from the project
root, but I haven't been anyway.
Add a note about production mode for npm installs.
Remove mention of envify since it is listed in package.json
Merge pull request #1793 from monsanto/browserify-note

Add a note about production mode for npm installs.
Add displayName to ReactTransitionGroup + friends

Fixes facebook/react-devtools#42.

Test Plan: Crossed fingers.
Merge pull request #1786 from zpao/react-tools-readme

Custom readme for react-tools
Merge pull request #1797 from spicyj/transition-group-names

Add displayName to ReactTransitionGroup + friends
Merge pull request #1784 from wvl/package-built-source-with-npm

Add the built source to npm package. See #1699