* Rename OnScreenGui module to ImGui
* Support multiple external module folders (closes#31)
* Cleaning up CMake files
* Restructure application specification
* Add parameter for library mode to all modules
* Add functions to handle global variable state
* Misc/remove warnings (#383)
* Increase build timeout and do a clean rebuild every commit
Add Property descriptions to the documentation file
Remove update method from StaticTranslation
Remove spelling error in RenderableGlobe
Remove rotation from renderablemodel projection
Fix setting the Origin through the GUI
Reorder Optional and documentation arguments for DocumentationEntry, and making Optional a non-optional argument
* Initial commit of satellites test branch
* Modified code to work with batch TLE files from online links specified in .mod file. Does not yet auto-download the files.
* Added debug function to mod file for testing static points in orbit
* Fixed time offset bug that was corrupting satellite positions
* Minor changes for debug output and camera position.
* Changed to circle billboard for rendering satellite position
* Added satellite group name to each renderable title, and keyboard shortcuts for toggling visibility
* Added support for using ghoul luasocket lib to download latest satellite TLE files from celestrak.com
* Adding reference to updated Ghoul submodule containing luasocket changes
* Updating reference to latest Ghoul submodule in feature/satellites
* Updated reference to new ghoul version
* Updated reference to new ghoul submodule version for satellites
* Updated reference to new ghoul submodule version for satellits
* Updated versions of TLE files
* Added new Lua-accessible downloader available for scene loading
* Improved error handling for TLE files
* Updated submodule reference for ext/ghoul prior to luasocket addition
* Update SGCT reference
