Planet switching support in presentations

[rphipps]

Overview: In Roscoe currently there is no support for planet switching between presentations. For example if there is a presentation on the Moon and if GE is currently on Earth it will run the presentation on Earth. We've worked around this on the default touchscreen by always switching to Earth when the presentation tab is clicked. This works for clients without presentations on other planets. There was also a work around for another client in which a rosnode listened for presentations being published by the director and matched on the slug to determine which planet to switch to whenever the presentation was clicked.

Requirements:

• Support presentations on each of the planets
• Add planet as a field to the presentation or scene (not sure which makes sense)
• When a presentation or scene is selected if the correct planet is not loaded then switch to the correct planet
• Work around timing issues with Earth to make this reliable, which may require greying out the touchscreen while the planet switches and delaying when a presentation starts with auto play so that the planet is fully loaded

Development notes Optional - list of places to look into and general guidelines (patterns to use, instructions and helpers)

Testing scenario Optional

If this task is testable - include list of commands and expected outputs.

[mikemerrill]

Based on the sort of thing NASM does, it seems it would be best to have this operate on a scene level.