The gitignore ** pattern is not supported by git until version 1.8.2.

CentOS 6 uses 1.7.1, Ubuntu 12.04 LTS uses 1.7.9.

https://github.com/git/git/blob/master/Documentation/RelNotes/1.8.2.txt
Merge pull request #1656 from GawainLynch/hotfix/gitignore

The gitignore ** pattern is not supported by git until version 1.8.2.
Better defaults for content that has no Title or contents.
Updated CKeditor to 4.4.4.
Updated Select2 to 3.5.1
Updated Underscore to 1.7.0
Updated Modernizr to 2.8.2
Merge branch 'master-org' into issue-1637