Let print answer if user can read responses.

Do not exit controller if user has read permissions over responses.
As so allow to print if setting "Participant may print answers" is set to true or if user has read permission over responses.
If not allowed, No echo, but send a 401

Suggested by Denis Chenu
Merge pull request #261 from gabrieljenik/patch-6

Fixed issue #9413 - Let print answer if user can read responses.