Add trio.StrictFIFOLock on sender.send_all
Support max_bytes argument on receive_some, keep track of write_ptr on receiver
Add max_bytes receive test test_ringbuf_max_bytes
Add docstrings to all ringbuf tests
Remove EFD_NONBLOCK support, not necesary anymore since we can use abandon_on_cancel=True on trio.to_thread.run_sync
Close eventfd's after usage on open_ringbuf
EventFD class now expects the fd to already be init with open_eventfd
RingBuff Sender and Receiver fully manage SharedMemory and EventFD lifecycles, no aditional ctx mngrs needed
Separate ring buf tests into its own test bed
Add parametrization to test and cancellation
Add docstrings
Add simple testing data gen module .samples