lua_filehelpers.cpp: Add lua script function 'cp()'

- Set Lua api version to 1.48


Origin commit data
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Commit: 270cd318ec
Author: Michael Liebmann <tuxcode.bbg@gmail.com>
Date: 2016-09-03 (Sat, 03 Sep 2016)

src/gui/lua/lua_filehelpers.h

@@ -39,6 +39,7 @@ class CLuaInstFileHelpers
 	private:
 		static CLuaFileHelpers *FileHelpersCheckData(lua_State *L, int n);
 		static int FileHelpersNew(lua_State *L);
+		static int FileHelpersCp(lua_State *L);
 		static int FileHelpersDelete(lua_State *L);
 };