mailto:... links are considered as outlinks and the registered url is something like http://piwik.org/mailto:...
Maybe adding 'mailto:' to the ftp:,https:,... would solve the problem.
See demo for Tuesday 25th March 2008.
Links were registered properly, but displaying
mailto was broken.
I think we don't need to change
Piwik_Common::isLookLikeUrl(), so I made additional case checking for
mailto: in link.