Hash table rendered as HTML source in test output

Using Edge [build #325](https://cleancoder.ci.cloudbees.com/job/fitnesse/325/).

1. Create a Slim test page with the following table:

    ```
    |script|hash test                                                               |
    |check |number of entries in;|!{fname:''Bob'', lname:''Martin'', today:!today}|3|
    ```

2. Doesn't appear to be strictly necessary but to ensure it doesn't interfere with the result, use the following fixture class:

    ```java
    import java.util.Map;
    
    public class HashTest {
    
        public int numberOfEntriesIn(Map<String,Object> map) {
            return map.size();
        }
    
    }
    ```

3. Run test on the page.

Now the output with latest Edge builds looks like:

![B20130412-325](http://i.imgur.com/Vnb7FtN.png)

While using Release [20121220](http://fitnesse.org/.FrontPage.FitNesseDevelopment.FitNesseRelease20121220):

![R20121220](http://i.imgur.com/5gm67NP.png)