Disable exit on error when checking if apache2.4 is installed.
Merge pull request #71 from RobertElder/fix-exit

Disable exit on error when checking if apache2.4 is installed.
Include base_dir in session namespaces.
Merge branch '2.5.x' of https://github.com/sourcefabric/Airtime into 2.5.x
Updates to selenium test suite; added test classes for basic UI functionality