Low: tests: Added test to verify sending ipc msg equal to max size succeeds
Low: ipcs: For shm ipc, always retry outstanding notifications when next event is sent
High: ringbuffer: Make max_size of ringbuffer accurate so shm ipc max msg size value is honored
Low: check_ipc.c: fix debug message to only display once.
Merge pull request #79 from davidvossel/master

fix shared memory ipc so max msg size is honored correctly