Added instructions for getting your credentials.
Add config file support.

Document how to obtain OAuth credentials (closes #8).
Add --debug option
Pass POST params as function parameters, not a dict.

This was a change to openphoto-python a long time ago,
to make it more "pythonic".

I suspect this fixes the rather odd error message in #19.
Merge pull request #21 from sneakypete81/config_files

Add config file support.
Merge pull request #22 from sneakypete81/param_fix

Pass POST params as function parameters, not a dict.
Merge pull request #23 from sneakypete81/logging

Add --debug option
Merge pull request #9 from dcancel/patch-1

Added instructions for getting your credentials.