manage a single connection to the relay for all of its games. Works
so far to the extent that the game's playable with all boards on the
same device (with checkins about to come) as long as all boards are
open. (Client doesn't handle opening closed games yet.)
which they're communicated to the device. Device is expected to have
a platform-specific notion of ID which the relay stores in a new
devices table and indexes with a 32-bit number which is returned to
the device -- which is encouraged but not required to use it in lieu
of the longer ID in future communications. Modify linux client and
test script to use the relay-supplied id. Some of this is commented
out for now.