Indicate to user that an error has occurred when processing form data

Fix for #1811 for the `facility` and `control_panel` apps.

We currently indicate to users at the form element that failed that there's an error.  This issue adds a top-of-page message to indicate to users the failure.

If this looks good, I believe doing this for all apps would be beneficial, and a good learning experience for less familiar developers.

![image](https://cloud.githubusercontent.com/assets/4072455/2568121/17b2d35e-b8de-11e3-846f-ce0d4bdf342f.png)