move utility stuff into sort and rename sort->util
start initial support for easily launching gambit-swank from emacs
add support for launching gambit-swank from emacs

Had to add some wrappers for swank-server-register! because it seems
that slime expects the port the swank is listening on to be written to a
special file that it reads from. A REPL can now be launched from within
emacs using the provided gambit-slime command.
clean up whitespace and modularize functions
add wrapper for swank:start-server so there's a single entry point
more formatting consistency
comment out source location functions (not set up)
fix swank:start-swank-server-in-thread

The previous implementation just started a new server in a new
thread. The new implementation gets the specified thread, interrupts it,
and starts a swank server on it. It still uses the standard port so it
might be necessary to double check this, but I think this implementation
more closely resembles intended functionality.
update readme for how to set up and launch servers