Refs #1823, several changes & tweaks to GeoIP modifications:

  * Renamed getVisitsByCity & getVisitsByRegion to getCity & getRegion.
  * Extra testing for anonymized IPs.
  * Show visitor city & region in visitor log & last visits widget.
  * Do specific check for apache module in checking for server based geoip implementation.
  * Fix for continent segment error.
  * Redesigned admin UI to be more compact & to show reason for broken implementations.
  * Don't show duplicate Unknowns in pretty location strings.
  * Don't use REMOTE_ADDR, instead get IP from Piwik_IP.


git-svn-id: http://dev.piwik.org/svn/trunk@7140 59fd770c-687e-43c8-a1e3-f5a4ff64c105