Use minimal-mistakes

• Write up simple user manual
• Write up manual on how to add new music via station developer
  • plus how to submit the data back to github

Use py2exe

Reproduce:

1. Have some garbage playin'
2. start a new station
3. GUI does not refreshes with the music it plays

Use py2app

Find some nice icon and add to the app

When the app is executed for the first time, we need to send user to the spotify page and have them authorize the access to their account.

Currently, it requires copy and pasting an URL from a browser into a terminal.

Steps:

1. run the app
2. Click Station | By composer
3. Click Cancel

Program crashes with:

Traceback (most recent call last):
  File "/.../spotify-classical-qt/src/MainWindow.py", line 264, in onNewStationByComposerPlay
    composer_id = self._station_by_composer_dlg._artist["id"]
AttributeError: 'StationByComposerDialog' object has no attribute '_artist'

Program should not crash and get back to the player.