Bug 18124: [Follow-up] Handle default parameters in a sub

Bug 18124: [Follow-up] Handle default parameters in a sub

Adds a internal routine to handle default values for the parameters
id and secret.
Also adds a parameter session_id for generate_csrf and check_csrf. This
session parameter is combined with the id parameter when generating or
checking a token.

Test plan:
Run t/Token.t

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>