Ability to draw all agents predictions at once, and to draw final plan
on top of samples. Reveals that IGP really is doing something sensible
here.
There's actually a name for this, of course: expected value.
Added ability to turn on/off all drawing elements. Drawing in layers,
also.
Not sure why this was here.
Rename MAP to plan since we might choose some other statistic like
expected value.
Ability to display all trajectories from a single sample at a time.
Samples are sorted by probability and can be cycled through.
Displays the weight of the sample.