Switch to using photo picker

[TheLastProject]

It's the new standard, let's use it:

https://developer.android.com/training/data-storage/shared/photopicker

I don't want to bother with auto-installing this stuff from Google Play Services, I personally dislike apps doing system-level things without permission. Just use it if available. We'll always use the picker for just one single image.

This will apply to all photo pickers. So:

• Adding a card from file on the + screen
• Setting an icon
• Setting a photo