More functionality and simplification.

-Added full name to possible user properties to edit
-Users can be added and deleted one at a time
-Passwords are generated if none is supplied for creation
-Added buildUserXML() which is shared by several functions (including upcoming ones)
-Shortened some function names and made variable names more consistent
-Renamed genString() (inherited from another program) to genPassword() and simplified it, then removed some characters which might be problematic
-Password generation defaults to 16 characters, which should be a reasonable default
Updated usage for new features.
This is v0.2.0.