Synchronize develop with master

 - Added link to COLLADA's official website.
 - Added comments to distinguish coordinates related to camera from
   coordinates related to the 3D model.
 - Changed single line comments to the corresponding bracket.
 - Made reference to the CU Macky Auditorium on its position.

* Removed outdated references to goworldwind.org website

* Modified reference to Tactical Symbols tutorials to include all of them

* Added updated reference to offline usage of tactical symbology

Remove configs for retired services