pyFileFixity v2.0.0 beta 2

Major milestone again, the codebase is now branch covered at more than 80%, which is honestly a great deal more than what I thought was possible to do for a first coverage. This score means that all core functions are covered, only a few specific arguments (like skipping missing files and such) are not (yet) tested, but apart from that, you can assume that files generated by this app are safe and stable.

This means that the application is now a lot more stable (and more crossplatform: files generated on one platform can now be used on any other platform, at least theoretically, but it's safe to say that files generated on Linux and Windows are totally compatible, for other platforms we need testers!), but this also means that some big changes had to be done in the inner workings of the app. Normally, ecc files generated with v2.0.0 beta 1 should still be compatible with beta 2, but if you have generated such ecc files, you should try them with beta 2 to ensure they still work, and if not, regenerate new ones.

From now on, the code should stay pretty much stable, and the high coverage score is here to ensure that.there won't be any regression.

Before the stable release, only a few new scripts need to be developped, like replication_repair.py (see TODO.md for more info).