SaVi satellite constellation visualizer savi-dev

Adding starlink simulation to list of files in Makefile.

Adding a simulation of SpaceX Starlink's inner shell (November 2018 filing, 550km altitude)

Removing superfluous syntactic sugar around winfo test commands.

don't need that eval.

Tweaking plot saving to save coverage map if
coverage window is open.

Tweaks to satplot output.
Time now works.
outputting .ppm, which works more consistently in Xfig.

Minor tweaks to the new ns-2 dump functionality.

Improved version of ns-2 dump capability.

Requires development sat-plot-scripts that
supports tabs.

names now supported.

(xfig may have trouble with first black in gifs?)

First cut at integration with satellite plot scripts.

Write satellites (number/lat/long) to sats.dump. If from
coverage window, save the background map. Still to do:
matching filenames for .gif and .dump
saving background map when coverage window is open
getting plot scripts to understand satellite names, not numbers
fixing loading of gifs in scripts (xfig doesn't like default gifs?)

Minor satellites list check - if there's not even a virtual sun,
don't dereference a NULL pointer from an empty list!