Make state.get_latest_config_filename a static method

This is to make it easier to use that method from other sources
Add a test suite for parsing .vcf files in our code

- Add a few sample vcf files for testing purposes
- Some changes to the CDContact class to ensure it can be
  instantiated standalone - without a folder or db instance
  tied to it.
Fix minor error in the bbdb test when cmd line argument is passed
Additional debug logs while logging into a CD server