more convenience methods.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@1353 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/FilePath.java

@@ -133,6 +133,10 @@ public final class FilePath {
         return local.exists();
     }
 
+    public boolean isDirectory() {
+        return local.isDirectory();
+    }
+
     /**
      * Always use {@link #getLocal()} or {@link #getRemote()}
      */