Add board layer view stack up sequence from front layer to back layer.

The old bottom to top layer stack up sequence from back to front layer was
only used for plotting so it was renamed appropriately.  This will be used
for future board object select disambiguation improvements.

pcbnew/dialogs/dialog_plot.cpp

@@ -104,7 +104,7 @@ DIALOG_PLOT::DIALOG_PLOT( PCB_EDIT_FRAME* aParent ) :
     std::vector<PCB_LAYER_ID> layersIdChoiceList;
     int                       textWidth = 0;
 
-    for( LSEQ seq = board->GetEnabledLayers().SeqStackupBottom2Top(); seq; ++seq )
+    for( LSEQ seq = board->GetEnabledLayers().SeqStackupForPlotting(); seq; ++seq )
     {
         PCB_LAYER_ID id = *seq;
         wxString     layerName = board->GetLayerName( id );
@@ -568,7 +568,7 @@ void DIALOG_PLOT::OnRightClickAllLayers( wxMouseEvent& event )
 
                 case ID_STACKUP_ORDER:
                 {
-                    LSEQ stackup = m_parent->GetBoard()->GetEnabledLayers().SeqStackupBottom2Top();
+                    LSEQ stackup = m_parent->GetBoard()->GetEnabledLayers().SeqStackupForPlotting();
                     arrangeAllLayersList( stackup );
                     m_plotAllLayersList->Select( -1 );
                     break;