dGame Precompiled header improvements (#876)

* moving branch

* Add deleteinven slash command

* Change name of BRICKS_IN_BBB

* Use string_view instead of strcmp

* Clean up include tree

* Remove unneeded headers from PCH files

Removes unneeded headers from pre-compiled headers.  This increases compile time, however reduces development time for most files.

* Update Entity.h

* Update EntityManager.h

* Update GameMessages.cpp

* There it compiles now

Co-authored-by: Aaron Kimbrell <aronwk.aaron@gmail.com>

dScripts/CppScripts.h

@@ -1,12 +1,13 @@
 #pragma once
-#include "dCommonVars.h"
-#include "MissionState.h"
+
+#include <cstdint>
 #include <string>
 #include <vector>
 
 class User;
 class Entity;
 class NiPoint3;
+enum class MissionState : int32_t;
 
 namespace CppScripts {
 	/**