invokes Release method of Dispatch interface of WIN32OLE object. Usually, you do not need to call
this method because Release method called automatically when WIN32OLE object garbaged.
static VALUE
fole_free(VALUE self)
{
struct oledata *pole = NULL;
pole = oledata_get_struct(self);
OLE_FREE(pole->pDispatch);
pole->pDispatch = NULL;
return Qnil;
}