modding: alt equipment (#6062)

Implements object_custom_equip objects that adds more support to have items modified by modders without having to export with hands or do xml edits to load hands. This is autonomous if exported as a object_custom_equip

Also adds non existing DisplayList for items that originally did not have a DisplayList. Longshot and Big Goron Sword Sheath is 2 examples

soh/src/code/z_player_lib.c

@@ -650,6 +650,7 @@ void Player_SetModels(Player* this, s32 modelGroup) {
     this->waistDLists = &sPlayerDListGroups[gPlayerModelTypes[modelGroup][4]][gSaveContext.linkAge];
 
     Player_SetModelsForHoldingShield(this);
+    GameInteractor_ExecuteOnPlayerSetModels(this, modelGroup);
 }
 
 void Player_SetModelGroup(Player* this, s32 modelGroup) {
@@ -1481,7 +1482,6 @@ s32 Player_OverrideLimbDrawGameplayFirstPerson(PlayState* play, s32 limbIndex, G
             *dList = NULL;
         }
     }
-
     return false;
 }