Use config, context, status and vcluster modules.

The main method of snf-deploy script will initialize them with
the args passed. Additionally make some minor changes related
to the command line:

 - snf-deploy all -> snf-deploy synnefo.
 - add --setup option
 - add --cluster option
 - use --<name>-dir for template, state, package dirs

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>