Warn if Makefile is out of date
Don't rebuild version.o if nothing has changed
Move msp retransmit time to #define'd const
Remember specified rate limit
Only use the best rtt calculation once per ack
Move rate limit code to separate file
Don't process MDP packets if the local address is invalid
Don't busy wait for forked processes to terminate
Remove respawn_on_crash behaviour, we aren't using or testing it
Rename TIME_NEVER... to TIME_MS_NEVER...
time_ms_to_timeval()
Improve MSP API

Replace struct msp_sock * with typedef MSP_SOCKET
Add new 'flags' arg to msp_socket(), unused for now
msp_send() returns ssize_t number of bytes sent; -1 for error
MSP handler returns size_t; number of bytes consumed
Add MSP_MESSAGE_SIZE definition
Rename msp_set_remote() to msp_connect()
msp_set_local(), msp_connect(), msp_listen(), msp_set_handler() all
return void
Improve MSP API

Replace struct msp_sock * with typedef MSP_SOCKET
Add new 'flags' arg to msp_socket(), unused for now
msp_send() returns ssize_t number of bytes sent; -1 for error
MSP handler returns size_t; number of bytes consumed
Add MSP_MESSAGE_SIZE definition
Rename msp_set_remote() to msp_connect()
msp_set_local(), msp_connect(), msp_listen(), msp_set_handler() all
return void