Feature: Add lexicon support for errors or chunk

[marten-dhm]

Please add support for lexicons or atleast for "score-threshold-not-met".
When a user that is not a spam robot incidentally triggers the error "score-threshold-not-met" he does not get any feedback and cannot continue or wil be confused of how to proceed.
Or better would be to be able to output a chunck.
In this chunk there can be a message that the user is suspected to be a robot and that he can contact the site admin with e-mail or phonenumber.