Pcbnew: fix read .kicad_pcb file error when an outdated plot parameter is...

Pcbnew: fix read .kicad_pcb file error when an outdated plot parameter is found. Now  outdated plot parameters are just ignored

pcbnew/pcb_plot_params.cpp

@@ -353,6 +353,8 @@ void PCB_PLOT_PARAMS_PARSER::Parse( PCB_PLOT_PARAMS* aPcbPlotParams )
         if( token == T_pcbplotparams )
             continue;
 
+        bool skip_right = false;
+
         switch( token )
         {
         case T_layerselection:
@@ -502,9 +504,12 @@ void PCB_PLOT_PARAMS_PARSER::Parse( PCB_PLOT_PARAMS* aPcbPlotParams )
             break;
 
         default:
-            skipCurrent();
+            skipCurrent();      // skip unknown or outdated plot parameter
+            skip_right = true;  // the closing right token is already read.
             break;
         }
+
+        if( ! skip_right )
             NeedRIGHT();
     }
 }