Revision 1205

(TableFrame.__init__): Add a panel
    object that can be used by derived classes to place any
    controls (including the grid) onto.
(QueryTableFrame.__init__): Use the panel as the parent window
    for all the controls. Reparent the grid so that the panel is
    the parent. Call UpdateStatusText() to correctly initialize
    the status bar.

(TableGrid.__init__): Create an
    instance variable to keep track of how many rows are selected.
    Subscribe once to the the events we are interested in.
(ThubanGrid.OnRangeSelect): Only handle event if event handling
    hasn't been turned off.
(ThubanGrid.OnSelectCell): Only handle event if event handling
    hasn't been turned off.
(ThubanGrid.ToggleEventListeners): Rather than subscribe None
    as an event listener (which changes the event handler stack)
    simply set an instance variable to False. This is checked in
    the event handlers.
(ThubanGrid.GetNumberSelected): Return the number of currently
    selected rows.
(TableFrame): Inherit from ThubanFrame so we can have a
    status bar and control buttons.
(QueryTableFrame.__init__): Create a status bar. Fixes RTbug #1942.
    Explicitly set which items are selected in the operator choice and
    action choice so there is always a valid selection. Fixes RTbug #1941.
    Subscribe to grid cell selection events so we can update the
    status bar.
(QueryTableFrame.UpdateStatusText): Update the status bar with
    how many rows are in the grid, how many columns, and how many
    rows are selected.
(QueryTableFrame.OnGridSelectRange, QueryTableFrame.OnGridSelectCell):
    Call UpdateStatusText when cells are (de)selected.
(QueryTableFrame.OnQuery): Use the string value in the value
    combo if either the selected item index is 0 or if the string
    cannot be found in the predefined list (this happens if the
    user changes the text). Fixes RTbug #1940.
    Only turn off the grid event listeners if there a query comes
    back with a none empty list of ids. in the case that the list
    is empty this causes a grid.ClearSelection() call to actually
    clear the grid selection which causes the selected items in
    the map to be deselected. Fixes RTbug #1939.