adsense 5.x-3.0

Changes since 5.x-3.0-beta2:

• Remove check for Drupal 6 version
• Removed parts that clobbered click tracking.
• *** empty log message ***
• Keywords were not logged in correctly for CSE search.
• Fix #332914: search doesn't work with clean URLs disabled
• Fix #305204: Use pubid instead of id in the settings path to prevent access denied by security filters
• Fix #339963: Allow 500px width for search results when ads are in top and bottom
• Fix #310539 by roychri: use !empty instead of isset when checking for slot ID use
• Add adsense class to the placeholder div
• Remove obsolete referral link from 5.x help files
• Add PHP visibility option
• Fix for #305204: use publisher instead of pubid
• Sync adsense_click with 6.x version. Minor coder fixes
• #361983 remove t() from define() as it causes performance issues
• Improve the status update warning messages.