Altered she-bang for my system and added .gitignore for .pyc files

Dear Joost,

Your readme shows that you can run the program with `python Excec.py`.
Personally I like to run it just with `./Excec.py`, however the she-bang did not work for me.
Is this also a problem on your system? If so, `#!/usr/bin/env python` works for me.

I also removed the compiled `.pyc` files from the repository and added a `.gitignore` to prevent them from appearing again. I suggest doing the same to prevent unnecessary diffs in your repo, as you do not need those files.

Best regards,
Bart