Addressed https://github.com/rubber/rubber/issues/177 issue.

This change addresses https://github.com/rubber/rubber/issues/177  
and https://bugs.launchpad.net/ubuntu/+source/ec2-ami-tools/+bug/1088540 issues. 

I pinned Ubuntu 13.04 repo only for ec2-ami-tools package to install latest package version.
Also added --no-filter switch for ec2-bundle-vol command to disable filtering for ssl keys and other files.