Bug 24862: Handle annonymous sessions gracefuly

Bug 24862: Handle annonymous sessions gracefuly

This patch introduces code to detect (cookie) annonymous sessions and
act as expected.

Right now, as check_cookie_auth is not passed the required permissions
(because there aren't always required permissions, and the code to check
permissions is shared with other authentication mechanisms) it returns
'ok' and the session id. This use case was overlooked when this was
coded, and yeilds unexpected error codes (500) when the user logs out
and the annonymous session cookie is used to hit the API. The end result
doesn't pose any security issue (i.e. the resource access is rejected)
but the returned error code is not correct and should be fixed.

This patch verifies for an anonymous session (and avoids querying the
corresponding patron) and then verifies if there is an authorization
config on the route and if the patron object is defined.

To test:
1. Apply the tests patch
2. Run:
   $ kshell
  k$ prove t/db_dependent/api/v1/auth_authenticate_api_request.t
=> FAIL: Tests fail, 500 instead of the expected 401
3. Apply this patch
4. Repeat 2
=> SUCCESS: Tests pass!
5. Repeat the original 'steps to reproduce' from the bug report using
   the browser
=> SUCCESS: Problem solved!
6. Sign off :-D

Sponsored-by: ByWater Solutions
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>