phlsys_choice: keep input on same line as prompt
fixup! Arcyd: maintain log of landed branches for gc'ing
Arcyd: test_shell - make accept.sh available

Add a new 'accept.sh' available in the 'test shell' environment so that
you can use 'poke.sh' to create new reviews and 'accept.sh' to accept
those reviews without going into the web interface.

Test Plan:
Poke and accept in
$ ./testbed/arcyd/test_shell.sh
barc gc: automatically prune landed branches

Test Plan:
poke, accept and gc in
$ ./testbed/arcyd/test_shell.sh

$ ./precommit.sh