76 tests. Implements the protocol directly rather than through pyparrot,
whose receive thread prints to stdout and would corrupt JSON-RPC.
Two corrections to the observed notes, both adopted: the emergency buffer
carries DATA_WITH_ACK with unlimited retries in libARController rather than
the low-latency type pyparrot sends, and fire-and-forget is the wrong
property for the command that cuts the motors; and the handshake reply must
be read until its NUL terminator rather than from a single recv, because it
has grown across firmware versions.
rsp2k
b044edbd87