This comments out some "if 0: debug()" stuff I keep around to investigate
problems, since lgtm thinks of it as accidentally-unreachable code.
I also deleted a server usage command
entirely (src/wormhole/server/cmd_usage.py show_usage) which was disabled
while I rewrote that schema: the new plan is to move the server into a new
repository altogether, and use a completely different approach to the
usage database.
