Keep lock while doing recycle_buffer
Pass context to main loop
Recycle WorkItems in a free list
Push and pull from the node data loop
Do async start/pause in alsa
Add alsa fds right after open.
Make a main-loop object with associated helper functions to handle async
methods.
rtloop -> data_loop
Handle async results a lot better.
Remove REMOVE_MEM command. We don't need it.
Handle stream memory updates better.