Allow commotion-splash to run without other commotion packages

* Fix query strings for xhtml themes
* Make the commotion/splash page independent of its parent
* Show apps link only if commotion-apps is installed

Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
checks for luci-commotion-apps instead of commotion-apps
Merge pull request #11 from opentechinstitute/no_luci_commotion

Tested and confirmed working per pull request test instructions.