Previously apache::mod::python and apache::mod::wsgi used
a case statement to determine which package to install. This
commit moves the package names to the params class and fixes
the syntax errors introduced in commit 2b79e8b when the
selectors were changed to include Scientific Linux.
This patch adds Scientific Linux to the various case statements so it is
supported. This also fixed the various templates so that the log location
is variable depending on weither the OS is Redhat based or Debian based.
