Midonet CLI: initial implementation

Includes:

  * design doc.
  * feature-complete CLI framework
  * partially implemented mappings to API objects/methods

Signed-off-by: Guillermo Ontanon <guillermo@midokura.jp>
CLI: update authentication code

Signed-off-by: Guillermo Ontanon <guillermo@midokura.jp>
Ignore dpkg-buildpackage byproducts

Signed-off-by: Guillermo Ontanon <guillermo@midokura.jp>