Tests failing due to Jetty problems

Apparently the latest update on Ubuntu 12.04 (12.04.3) includes a library that Jetty is not happy with:

http://askubuntu.com/questions/377021/solr-jetty-on-ubuntu-12-04-3

To fix it we need to install the following package:

```
apt-get install libcommons-fileupload-java:amd64=1.2.2-1
```

Should this go into the install instructions?