Debugging for Travis build

Addresses #630
Point Travis Jetty at correct location of JDK

Addresses #630
Merge branch 'develop' into 198-homepage_banner
Added a ga_campaign_params template tag

Added a template tag for generating the query parameters for a Google
Analytics Custom campaign.

I'll need this to support analytics and A/B testing with the banner.

In order to test this, I refined the SettingsChangingTestCase.
Clean up use of SettingsChangingTestCase

Use the set_setting method instead of this sloppy setting changing
set up.

Also, the inheritance order was whack, even though it didn't really matter
in this case.