Ubuntu builder.
Allow specifying username when building images.
First pass at ubuntu builder.
Directory structure.
lint
Switch to using manifest files for building images.
'set -e' for fedora slave init script.
Add libssl-dev/openssl-devel to builders.
lint
Adapt promote-iamges to new world order.
Merge pull request #39 from ClusterHQ/ubuntu-builder

[FLOC-1047] Add a Ubuntu builder.