cli: introducing FiniteStateMachine (2/2)

this patch:

- completes state management cycle.
- moves visualisation experience away from the shell/commands
  to the state callbacks making engineshell only maintainer.

Change-Id: Ia739a5484b83ebd4cbdf0c4fabf7e763a20fa58f
Signed-off-by: Michael pasternak <mpastern@redhat.com>