- fixed #9 referer URLs with host registered as main_url or alias_url should NOT be counted as referer
now if a visitor comes to piwik.org/ with a piwik.org/xx/y/z referer, it will be considered a direct entry rather than a referer visit.
makes use of the new caching mechanism introduced with the Goal Tracking plugin, to cache website-related data for super fast access at Tracker time.
- Goals is not a tracker plugin anymore (improving performance of Tracker)
- fixed bug that the cache file wasn't read properly and goal queries were done at each piwik.php request


git-svn-id: http://dev.piwik.org/svn/trunk@994 59fd770c-687e-43c8-a1e3-f5a4ff64c105