Fix display of bases in show_observation
Fix display of bases in show_observation

They had no right-hand limit, so caused scrolling to the right indefinitely.  See https://www.pivotaltracker.com/story/show/152023063

Fix is to limit text width, which makes them continue to next line when that width is exceeded.
Also align top of *Bases* caption with top of bases.

JoeCohen/mushroom-observer,JoeCohen/mushroom-observer,MushroomObserver/mushroom-observer,JoeCohen/mushroom-observer,JoeCohen/mushroom-observer,JoeCohen/mushroom-observer,JoeCohen/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,JoeCohen/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer