Check if the array index params exists.
Check if the array index params exists.

To prevent an E_NOTICE error a check was introduce. If the index does not exists it will be setted to null.
The notice occurs when the URI will be called without a slash behind the controller.

Signed-off-by: Mario Kellner <bd3db686f9fb0eadc95a496deaf136b0abcb2beb@studmail.w-hs.de>

mbarquin/slim-dynamic-routing