Major refactoring of the code:

* Changed python function names to be more pythonesque (i.e.: addData -> add_data).
* Changed some file names to be more consistent across the project.
* Moved the tests to their respective python file.
* Removed the tests files that are no longer necessary.
* Modified Makefile accordingly.

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>