Added new game mode COUNTERWIN.

Improved add_extra_msg_file function to use "English" as the fallback
language for loading msg files (#256)

artifacts/scripting/headers/define_extra.h

@@ -31,7 +31,7 @@
 
 #define WEAPON_BIGGUN         256  // 0x00000100 - Big Gun
 #define WEAPON_2HAND          512  // 0x00000200 - 2Hnd (weapon is two-handed)
-#define WEAPON_ENERGYWEAPON  1024  // 0x00000400 - Energy Weapon (forces weapon to use Energy Weapons skill)
+#define WEAPON_ENERGY        1024  // 0x00000400 - Energy Weapon (forces weapon to use Energy Weapons skill)
 
 #define ATKMODE_PRI_NONE        0
 #define ATKMODE_PRI_PUNCH       1  // 0001

artifacts/scripting/headers/sfall.h

@@ -19,6 +19,7 @@
 #define BARTER      (0x20000)
 #define HEROWIN     (0x40000)
 #define DIALOGVIEW  (0x80000)
+#define COUNTERWIN  (0x100000) // counter window for moving multiple items or setting a timer
 
 //Valid arguments to register_hook
 #define HOOK_TOHIT            (0)

artifacts/scripting/sfall function notes.txt

@@ -613,6 +613,7 @@ optional arguments:
 > int sfall_func2("add_extra_msg_file", string fileName, int fileNumber)
 - loads the custom message file, and returns the file ID number assigned to it in range from 0x3000 to 0x3FFF for the message_str_game function to get messages from the file
 - fileName: the name of the custom message file (including the .msg extension) in "text\<language>\game\" directory
+- NOTE: if the msg file does not exist in the current language directory, the function will try to load it from "text\English\game\" directory
 optional argument:
 - fileNumber: the file ID number for the message_str_game function. The available range is from 0x2000 to 0x2FFF (see ExtraGameMsgFileList setting in ddraw.ini)
   use fileNumber only if you want to add a message file without editing ddraw.ini or existing scripts to support the old way