SaVi satellite constellation visualizer savi-dev

Adding in a 'tropics' flag and checkbox in coverage, to show the Tropics of Cancer and Capricorn.
This can be altered in the Simulation Constants dialog.

Not supporting cylindrical/spherical projections yet, because the trig manipulation escapes me.
So it's unprojected only for now.

Noting unicode support prototype.
Likely a dead end.

Forcing equatorial plane on for equatorial systems.

Minor demonstration of how Unicode support might be done.
Looks painful, but is backwards compatible, easy to override.

lower-case minor text fix.

Adding in option to show equator in coverage view,
with new checkbox/menu option.

This is synced to the equatorial plane view in Geomview.

(Should have gotten this working loooong ago - turned
out to be much easier than I had thought.)

Noting unsuccessful unicode experiments.

Updating year, but this is really an excuse to
try to sort out Id tags at client end.

Fixing previous commit to mke it useful.
Problem was updating the sunlight color by
clicking on the color weel -- since it's
drawn as satellie coverage, force a redraw.

adding in updates for when you change colors in
color wells while simulation stopped.