Fixed RSysLog dependency in order to support Ubuntu v14.04

Currently there is a dependency to cookbook RSysLog v1.5.0, however, that version does not yet support Ubuntu's latest LTS-version 14.04, as, it does not use Ubuntu's Upstart-provider to restart the RSysLog-daemon.
This issue has been fixed in RSysLog cookbook v1.12.2 (see opscode-cookbooks/rsyslog@5e341d0). Thus, the dependency should reflect that version.
Tested provisioning with AWS Ubuntu v12.04 and AWS Ubuntu v14.04.