Sets current codepage. The WIN32OLE.codepage is initialized according
to Encoding.default_internal. If Encoding.default_internal is nil then WIN32OLE.codepage is initialized
according to Encoding.default_external.
static VALUE
fole_s_set_code_page(VALUE self, VALUE vcp)
{
UINT cp = FIX2INT(vcp);
set_ole_codepage(cp);
/*
* Should this method return old codepage?
*/
return Qnil;
}