add check for selectable scatterternary trace:

- only scatterternary traces with mode 'markers' or/and 'text'
  can be selected

Author: etpinard

src/components/modebar/manage.js

@@ -173,7 +173,7 @@ function isSelectable(fullData) {
 
         if(!trace._module || !trace._module.selectPoints) continue;
 
-        if(trace.type === 'scatter') {
+        if(trace.type === 'scatter' || trace.type === 'scatterternary') {
             if(scatterSubTypes.hasMarkers(trace) || scatterSubTypes.hasText(trace)) {
                 selectable = true;
             }