Fill in gitignore
Basic java implementation of volunteer notifications of appointments.

This commit has been squashed from several previous commits to eliminate
some API keys which were accidentally committed. It implements basic
volunteer notifications in response to posts, and allows volunteers
and patients to create profiles specifying their locations and some
other preferences.

Note that the code is not exactly exemplar -- if I'd realized early
on how much scope creep I'd add, I would have at least pulled in
Spring or Wicket.