Mcdeck

- New: added a tool for installing/uninstalling .zip file card sets
- New: added a default path setting for .zip card sets in settings dialog

- New: drag & drop of .o8d files
- New: import OCTGN .o8d files
- New: import/browse cards from a local OCTGN installation
- New: use local OCTGN images (if available) if MarvelCDB has no image
- New: import cards/decks from MarvelCDB (placeholder if no image available)
- New: replace front image on selected card(s)

- Fix: launch with 'python -m mcdeck.script' instead due to setuptools/pip
not playing nice with installing a __main__.py file

- New: script can also be launched with 'python -m mcdeck'
- Fix: information in Readme.md about how to launch the software

- New: added export of OCTGN card set(s)