Remove adp.pass.py.  Make adp.py prompt for the password if not supplied on the command line.
Avoid making requests for already downloaded pay stubs

I keep a backup of my pay stubs.  This reduces the time for the script to download new pay stubs from over a minute to a few seconds.
Merge pull request #1 from lovrop/master

Merge adp.pass.py and adp.py, make faster when most pay stubs already downloaded