Function:   GetScreen()

               GetScreen() retrieves text from a screen portion and returns
               it in a memo variable. Just like GetText() but with more
               lines.

   Syntax:     GetScreen([nTop,nLeft,nBottom,nRight]) --> cMemo

   Arguments:  The screen portion to retrive. when omitted it defaults
               to the whole screen.

   Returns:    The screen portion as a Memo.

   Usage:      /* Get whole screen */
               ScrMemo := GetScreen()