Comment out seemingly unnecessary trampoline()

The underlying socket.read() will trampoline() automatically if necessary. It
should *not* be necessary to explicitly trampoline when using green sockets.
Remove FIXME tag

This is not a FIXME anymore.
Rename module Queue -> queue

Module names should be lower case.
Add param to gyield() to allow not switching back
Move tests to a top-level package

This may be a cleaner way to organize all tests.
Add test for threads
Add test for threading.active_count()
Make threading.active_count "private"

This variable is not intended to be accessed outside of the module.
Check to ensure that we're dealing with "green" threads
Fix inline comments
Add support for Loop.handles

Loop.handles now returns a list of all active handles associated with the loop.

- void *data is declared in uv_handle_s
- Pointer affinity has been made consistent
- Inline comments and docstrings have been clarified
- Private variables have been renamed for clarity
Add __repr__ with extended info
Convert address to hex early
Rename arg in nested func to avoid name shadowing
Ensure prepare_h is refd when a callback is added
Add test for threading.Condition and patch threading.RLock

This ensures that condition variables work as expected. In addition, it is
necessary to patch threading.RLock so that threading.Condition works as
expected.
Bump version
Fix incorrect module injection (thread -> _thread)
Bump version and add test docstring
Remove comment which probably no longer applies