OTRGlobals cleanup (#4251)

* Remove unused headers

* Move all "ResourceMgr_" functions to a new file

* Don't transitively include SaveManager

* Move cvar prefixes to a new header

* Add missing includes

* Update OTRGlobals.cpp

* Fix build

* Address review

* Fix some of the errors

* Update gameplaystats.h

* Update z_en_in.c

* Hopefully fix the linux issues

* Fix Linux issues for real this time, I checked

* Update ResourceManagerHelpers.cpp

* Update z_obj_mure2.c

* Post-merge fixes

* Fix build (hopefully)

* Post-merge fixes

* Update z_file_nameset_PAL.c

* cleanup some unnecessary headers (#7)

---------

Co-authored-by: Archez <Archez@users.noreply.github.com>

soh/src/code/z_play.c

@@ -11,6 +11,8 @@
 #include <overlays/misc/ovl_kaleido_scope/z_kaleido_scope.h>
 #include "soh/Enhancements/enhancementTypes.h"
 #include "soh/Enhancements/game-interactor/GameInteractor_Hooks.h"
+#include "soh/OTRGlobals.h"
+#include "soh/SaveManager.h"
 #include "soh/framebuffer_effects.h"
 
 #include <libultraship/libultraship.h>