Crypto mode for pappy now works. Still need to work out the kinks
for not supplying a project file to `pappy -c`, but when supplied
encryption and decryption work.
Project is now properly encrypting the archive,
and now I just need to ensure proper decryption
is happening. Also need to work on cleaning up
clear text versions of the crypt project files.
Need to write tests for flushing out edge cases.
Converted the crypto and compression plugins to core features, and
added the utility variables and functions to the Config class in
``config.py``. Added helper functions in PappySession class in
``pappy.py`` to enable the user to pass in an encrypted project archive.
Next moving to testing and debugging!
Nich