Make background for the viewport

[mattdelsordo]

I want to have some static image in the background of the main viewport to make it look like the Friendo + dogs are actually standing in some sort of space. Something a la Nintendogs, maybe in crayon? And then scan it in.

[mattdelsordo]

Add (maybe unlockable) options for the backdrop, maybe based on existing emojis that can be used for the selector in the UI. Ideas:
🏡: American residential living room (default)
🌋: Lava room (for fire guys)
⛰️: mountain (earth)
🌊: under the sea (water)
☁️: cloud zone (air)

🏔️: Snow landscape/swiss chalet?
🏖️: Beach
🏕️/🏞️: Camping/wilderness
🏛️: Greek temple
🏰: Castle? Gothic architecture
🌉: Urban setting
🌌/🛸: SPAAAACE