Renaming Script Contexts

- Determined how the various script contexts were used and renamed accordingly.
- ScriptContext2_Enable/Disable => Lock/UnlockPlayerFieldControls - The sole purpose of the flag is to make sure the player can't move around in the overworld. It has nothing to do with script contexts.
- ScriptContext1 => ScriptContext - It is the global script context used to set up scripts which run over many frames.
- ScriptContext2_RunNewScript => RunScriptImmediately - ScriptContext2's sole purpose was to run scripts immediately and in a separate context, usually while the global context is waiting for things like map loads or screen changes.

src/field_poison.c

@@ -98,7 +98,7 @@ static void Task_TryFieldPoisonWhiteOut(u8 taskId)
             {
                 gSpecialVar_Result = FLDPSN_NO_WHITEOUT;
             }
-            EnableBothScriptContexts();
+            ScriptContext_Enable();
             DestroyTask(taskId);
             break;
     }
@@ -110,7 +110,7 @@ static void Task_TryFieldPoisonWhiteOut(u8 taskId)
 void TryFieldPoisonWhiteOut(void)
 {
     CreateTask(Task_TryFieldPoisonWhiteOut, 80);
-    ScriptContext1_Stop();
+    ScriptContext_Stop();
 }
 
 s32 DoPoisonFieldEffect(void)