Core/Game: Include cleanup

* Mostly aimed at removing Log/DatabaseEnv includes from other headers
* Fix most packet headers including other packet headers - moved common structures such as ItemInstance to their own files
* Moved SAI function definitions to source files (massive or requiring many different dependencies)

src/server/game/Reputation/ReputationMgr.h

@@ -22,7 +22,7 @@
 #include "Common.h"
 #include "SharedDefines.h"
 #include "Language.h"
-#include "QueryResult.h"
+#include "DatabaseEnvFwd.h"
 #include <map>
 
 struct FactionEntry;