avoid having the description that's too long, which pushes the scroll bar too far off.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@13011 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/model/Label.java

@@ -81,6 +81,10 @@ public class Label implements Comparable<Label>, ModelObject {
         StringBuilder buf = new StringBuilder("group of ");
         boolean first=true;
         for (Node n : nodes) {
+            if(buf.length()>80) {
+                buf.append(",...");
+                break;
+            }
             if(!first)  buf.append(',');
             else        first=false;
             buf.append(n.getNodeName());