Allow wildcard domain for 3rd party cookies to be set explicitly in conf...

Pull request for the enhancements as discussed in this thread: http://forum.piwik.org/read.php?2,107159,page=1#msg-107379

My last pull request let the tests fail. Maybe it is due to the tests do not take into account that method signature(s) have changed, especially in Cookie.php, l.86. Unfortunately I do not know where and what to adapt and what exactly failed, due to I cannot find any details in Travis overview.
Help will be appreciated.