updating rails to 3.2.10 in response to CVE-2012-5664

See also:
https://github.com/gitlabhq/gitlabhq/issues/2464
http://www.securityfocus.com/bid/57084
Merge pull request #2494 from dvanduzer/4-0-stable

updating rails to 3.2.10 in response to CVE-2012-5664