libuv support broken on Ubuntu 16.04 and with libwebsockets 3.0

[rdumusc]

• Ubuntu 16.04 with libuv 0.10-dev
• Compiled libwebsockets v3.0-stable with LWS_WITH_LIBUV=ON

Two functions are missing, one in libuv and one in lws 3.0:

1) ../Rockets/rockets/serverContext.cpp:59:63: error: ‘uv_loop_alive’ was not declared in this scope const bool uvLoopRunning = uvLoop && uv_loopalive(uvLoop) != 0;

2) ../Rockets/rockets/serverContext.cpp:92:44: error: ‘lws_uv_initloop’ was not declared in this scope lws_uvinitloop(context, uvLoop, 0);

lws 3.0 API: https://libwebsockets.org/lws-api-doc-v3.0-stable/html/group__uv.html