Backport fix for CVE-2014-3482

Also adds a test to ensure SQL injection is not possible via range
queries (Rails 2.3 is not affected, was CVE-2014-3483 for 4.x)
Update to Rails LTS 2.3.18.11
Improve release workflow
Remove .gem files from repository
Release Rails LTS 2.3.18.11
Improve community release process