NetworkTable interface: Provide method to set persistent filename.

java/src/edu/wpi/first/wpilibj/networktables/NetworkTable.java

@@ -112,6 +112,18 @@ public class NetworkTable implements ITable, IRemote {
     port = aport;
   }
 
+  /**
+   * Sets the persistent filename.
+   * @param filename the filename that the network tables server uses for
+   * automatic loading and saving of persistent values
+   */
+  public synchronized static void setPersistentFilename(final String filename) {
+    if (persistentFilename == filename)
+      return;
+    checkInit();
+    persistentFilename = filename;
+  }
+
   /**
    * Sets the network identity.
    * This is provided in the connection info on the remote end.