esp32-event

This is a libuv-like eventloop library that monitors sockets for I/O events, implements timers and a message queue. The API is designed to be API compatible with the core libuv API - uv_loop_t, uv_timer_t, uv_poll_t, uv_async_t. Additionally, it has a 'control channel' that can wake up the event loop and pass it a message. uv_async_t is implemented on top of that mechanism, but it also allows marshalling arbitrary function calls via a message queue. A C++11 wrapper is implemented on top of that that makes things more convenient and also allows the caller thread to wait for the eventloop thread to return a value, thus implementing synchronous marshalling.