Major new features/rewrites

 * add our own encrypted file backend (cipher.py and cryptfile.py)
 * refactor server.py, fix detach/eval, add -k to kill current server
 * s/getpass bugs
 * tests for cryptfile and the request handler
 * protocol: rename read/write to recvMsg/sendMsg
remove emacs save file
add comments
split bin/keyagent_server out of server.py, refactor, more tests
stop tests leaving files around
getKeyFile finds keys in /home/shoemaker/.keyagent/keys
chmod
typos