Removed CakePHP Google Group and put that in a new CakePHP Official Communities section where added popular community link with the previously written google group.
Merge remote-tracking branch 'upstream/master'
Fix broken link http://cakephp.org/feeds and updated this community link with the documentation where to get help section.
Modified according to https://github.com/cakephp/docs/pull/829#discussion-diff-7081295 and https://github.com/cakephp/docs/pull/829#discussion-diff-7081298
Merge pull request #829 from shahariaazam/master

Removed CakePHP Google Group and put that in a new CakePHP Official Communities section