Normalize DefaultDOMPropertyConfig

For consistency, use lowerCamelCase for all props in `DefaultDOMPropertyConfig`.
Remove remaining calls to ReactCompositeComponent.autoBind.

This is causing console.warning spew in the open source tests.
Use populist v0.1.2 to bundle test modules instead of browserify.

This will allow full support for mocking, dumpCache, and correct line
numbers in error messages.
Call require("mock-modules").register in every mockable module.

Mocking happens only when config.constants.__MOCK__ is true.
Enable module.exports mocking in react-test.js.

We don't currently attempt to mock modules automatically, but we do
respect require("mock-modules").mock, .dontMock, and .dumpCache.

I'm going to keep investigating auto-mocking, since that would move us
much closer to the behavior used within Facebook.

Closes #154.
Closes #155.
Store dirtyMocks array globally so it can survive dumpCache().

When require("mock-modules").dumpCache() is called, all mock functions
previously created continue to refer to the old dirtyMocks array.

If we replace that array with a new one, those mock functions will never
have their .mockClear() methods called again.

The upstream version of mocks.js pulls a similar global trick, and I never
understood why until now.