Small changes

Added some stuff to patientController. Rejiggled method in
DatabaseHandler.

Should really change DatabaseHandler to deal with prepared statements.
Some of the strings are starting to look nasty.
Mostly filled servlets.

Most of the needed methods for the servlets have been filled out. The
trick now is remembering what I called the parameters, so I don't mess
up the views.

Stuff to do:
1. Views
2. Better error handling
3. Diagrams and stuff
4. modify database so duplicates are noted with a quantity column
(maybe)