We will continue using `bin/jsx-internal`, well, internally.
Note that this version no longer respects `@providesModule`, and it
doesn't do anything special with constants like `__DEV__`, so we can no
longer get to claim that `bin/jsx` can be used to build the core.
I'm happy about this, personally, because it demonstrates the flexibility
of Commoner.
No longer injecting __MOCK__ as a global constant (it's just a config
property now).
Turns out the `grunt jsx:debug` task was never necessary for tests.