Added libua name detection so it would find the .a on Linux (Ubuntu 12.04).
Removed loop::ref() and loop::unref(), since they are not compatible with current libuv upstream master (5d92ccce9466dbfe8a613d0ee5ded1a959014554) and are not used in test codes.
Merge pull request #13 from kennethho/master

To link libuv on Linux (Ubuntu 12.04) and sync with libuv upstream