Fix string formatting in TestCases.ValidWildcard.

The "%" formatting operator has a higher precedence than the "+" operator.
This results in an unhelpful exception if a TLD is passed in.
Add a .gitignore.
Start cleanup of source.

Ran "autopep8 --experimental -a -r -i ."

src/TestCases.py: Conversion of some comments to docstrings.
Merge pull request #1 from coruus/master

Fix string formatting in TestCases.ValidWildcard.