- Along with rebasing the code it became nessecary to update various
calls to `scenery_small_entry_has_flag` and `EntityBase`.
- Added a new window theme with default colours.
- Fixed bug with see-through supports not working.
- Removed incomplete "ride exclusions" tab
- Removed unused text string (Ride Exclusions)
Define see-through paint colours in Paint.h for global use
Color staff sprite button
Change ride->is_visible bool to ignore_invisible_flag bool
Add shortcut to open transparency options (CTRL+T)
- Changes all references of `VIEWPORT_FLAG_INVISIBLE_PEEPS` to `VIEWPORT_FLAG_INVISIBLE_GUESTS` and `VIEWPORT_FLAG_INVISIBLE_STAFF`
- Updates Invisible People menu item and shortcut.
- Added new viewport flags into the `viewport_set_visibility` function
- Invisible options only work if see-through is activated as well
- Added see-through supports
- Regression: Exclude ride from invisible no longer works (ride is still see-through)
