init: Provide $DESC.
limitfiles: Import global modules from main().

This makes it possible to call main() from other code to launch the
daemon.
limitfiles: Add documentation.

This documents the contents of the module so people might use it as a
library if they wish.  It also helps people use the software in case
it gets detached from the README.
doc: Add Sphinx configuration.

I generated the documentation with Sphinx just because it seemed like
the easiest way to make sure my markup looked nice.  But since I went
through the trouble of making the configuration, I figure I might as
well commit it.
limitfiles: Increment version; follow PEP 8.
setup: Install baseline umask.

This helps the installer work correctly if the user has a stricter
umask.
setup: Better support source distributions.

Being able to send tar files is handy for testing.