Update libuv API for node 0.8.

Node 0.8 refs/unrefs the event loop on a per-handle basis.
remove usb_ids
Build with gyp; NPM package.json
Remove broken examples (need to add new examples for new API)
Move tests to mocha
Fix issue #1 : match CompletionData int type to libusb
Fix another compiler error from clang
Add test for error handling
Version bump: 0.1.1
Compatibility with Node 0.9.5.

Signature of libuv's uv_after_work_cb callback function pointer changed.
Easiest backwards-compatible way to handle this is to cast the function
pointer.
Remove unnecessary x86-specific compiler flag -msse2. Fixes #2.
0.1.2
Update on master