fixed bug where queued ships would all finish building at once
fixed bug where outlines around a ship wouldn't scale with zooming
fixed bug where dragging a Satellite in the game designer would not draw the new orbit properly
small refactor of Orbit
refactor SystemViewer to offer choice of planet type before placing the planet; also making it rely less on values of OwnableSatelliteType
adding some serialVersionUIDs to shut up warnings
refactoring SystemViewer's selection system to actually return an object instead of assigning to a member and throwing an exception when nothing is found - there's nothing exceptional about finding nothing.