Implemented new GUI component to handle WMS servers
* Add Lua scripts to support adding GIBS datasets (closes#222)
* Add Lua function to load WMS servers from a predefined file
* Workaround for Visual Studio 15.3 compile fix in Windows headers
* Initial support for parsing GetCapabilities file and automatically add layers
* Add a Trigger property to remove a layer
* Support default servers
* Add default file
* Move WMS server code from GUI component into GlobeBrowsingModule
* Add Lua scripts for loading and removing WMS servers
Automatically load default servers on startup
* Reset tile provider before removing a layer tolimit the crash risk
Add "From focus" button to switch globebrowsing gui to the same node as the focus
* Remove warnings
Remove compile error with nonexisting GDALOpenEx function
* 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
* 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
