- Now there is only one solution that contains both GodotSharp and GodotSharpEditor project. Previously we had one solution for each project
- GodotSharpEditor reference GodotShatp with a 'ProjectReference'. Previously it was a 'Reference' to the assembly
- This also simplifies the command line option to generate this solution: 'godot --generate-cs-api <OutputDir>'
Using `misc/scripts/fix_headers.py` on all Godot files.
Some missing header guards were added, and the header inclusion order
was fixed in the Bullet module.