Increased accuracy of map zooming
Added Parse library

The default .gitignore doesn't ignore .html files or javadocs, so I'm
not sure if all this should be committed.  I guess it can always be
removed & ignored later.
Initial login with registration

Replaced hardcoded login with initial Parse-based login.  Created
RegistrationActivity with no function.
Implement new user registration

Also implemented auto-login following successful registration.
Also moved Parse.initialize() into an Application subclass.