[Celestia-developers] Some small changes

[Chris L. <cl...@ww...>]

I've made a number of small checkins tonight . . .

At Grant's request, I added a texture map (medium and low res versions) 
for Enceladus.  The map is a slightly modified version of Phil Stooke's 
mosaic; the only change was filling a small gap in the south polar area.

I implemented different symbols for markers.  The only way to choose a 
symbol other than the default diamond is to use the script command mark.  
The command now takes a parameter symbol that can be one of the following 
strings: diamond, plus, square, x, or triangle.

I fixed the 'blue galaxies' bug, caused by interactions between nebula and 
galaxy add-ons.

And, I changed M82 to M81 in the base galaxies file; Selden noticed that 
mistake.

--Chris