PR for #6866 - Allow console specific view manager configuration

Allow to override "display_exceptions" and "display_not_found_reason" for Console ViewManager #6866
I am also not sure if runtime-merging (and thus destroying the possibility of accessing original config) is a good idea.

Another point: We should definitly use `Stdlib\ArrayUtils::merge()` instead of plain old `array_merge()` to keep full power of configuration merge (see #6899, #6903)!