Merge pull request #43 from nikicat/master

migrated from docopt to click
fixed "status --diff" when Container.id is None
actions.images: code style fix
added "ships list" and "ships restart" commands
removed "image needs to be rebuilt" check
SourceImage.gethash: removed intermidiate hashing for file content
added Tasks
chaining for "containers" subgroup support
basic logfile support (log files are now viewable using ssh+less)