Added comment about a warning, no functional change.

git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1649930 13f79535-47bb-0310-9956-ffa450edef68

framework/start/src/org/ofbiz/base/start/Classpath.java

@@ -60,6 +60,7 @@ public boolean addComponent(File component) {
                         return true;
                     }
                 } else {
+                    // In most cases, this warning can be ignored. The JRE-supplied class path may include non-existent paths.
                     System.out.println("Warning : Module classpath component '" + component + "' is not valid and will be ignored...");
                 }
             } catch (IOException e) {}