Revert "Exit and display error msg when no config.php file is found"

This doesn't work from the frontend ajax calls. Need to figure out some
other way to fail more gracefully.

This reverts commit 696d8932174c9472917c6499de4ac781e5f46482.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>