graphics/impressive: Update to 0.12.1

• Remove patch for impressive.py that no longer applies. [1]

Changelog:

• Fixed crash in crash reporter with recent Pillow versions [1]
• Fixed crash with recent PyGame versions when non-latin characters appeared in slide titles
• Fixed page rotation
• Fixed -x/--fade mode
• Fixed directory playback mode
• More robust PDF hyperlink parser (page boxes can now be PDF references)
• Added option to temporarily inhibit automatic slideshows
• Default keybinding: [A] key, actions: auto-start, auto-stop, auto-toggle

MFH: 2019Q3