Add command line arguments for --develop, --load-save, and --stage

[jdflyer]

This PR adds 3 new command line arguments to dusklight that are designed to speed up development.

• --develop: Sets mDoMain::developmentMode to true and enables dusk::OSReportReallyForceEnable (The same behavior as the original development mode)
• --load-save launches dusklight into a specified save from the existing savefile. It overrides the scene change function in d_s_logo and loads the save and goes straight to the play scene
• --stage launches dusklight into a specified stage with the following format: STAGE,ROOM,POINT,LAYER with the last few parameters being optional. This is implemented in the same function as --load-save and the two work together.