Unittests

Hi,

I have created a small set of unittests to have a better control of the changes.

To run them it is very easy, just: python -m unittest on the top folder of the project.

Note that as supposed by the .gitignore, that you need a configuration file "regapp_tools.conf" on the local folder.

Related to the issue #2 (closed), one of them: "test_username_from_subiss_test_egi" is taking my subiss from egi and testing it is converted to the expected username (failing for now...). It needs to modify on the line 39 what is the expected value after the conversion.