[xwiki-devs] Upgrade FF version to 6 on jenkins agents

Hi devs, Since 1) we are currently testing only on one browser (FF 3.6 right now) and 2) since FF 6 is now the mainstream version and since 3) we have an issue with latest selenium2 and FF 3.7 (see http://code.google.com/p/selenium/issues/detail?id=2320), I propose to update our agents to use FF 6.0. I'm going to proceed so shout if you don't agree. Thanks -Vincent