Add optional scrall parse for xsm files

[modelint]

Add an option to pass along to the xsm parser to turn scrall parsing on and off
Turning it off will speed up state machine parshing to get a drawing quickly
This can be useful in the early phases of drafting a state machine

[modelint]

We should also use a special shading, coloring or other visual cue on the activity compartments that are not parsed!