Fix strict standards errors in processors, success() signature not matching

Fixes https://github.com/lossendae/BigBrother/issues/32

not sure about the comment from @rtripault which says this should be fixed in master branch. With the proposed changes, the signature of success() matches the one from modProcessor and the extra works again. Would be nice to have a new release with this fix soon as my hoster switched to PHP 5.4 (as lowest PHP version) and BigBrother is not working on any installs anymore.