bin: add --vm-start-paused to hosted-engine

Allow to start the hosted engine VM qith qemu paused.

Change-Id: I749e877fe1fb259b99f1dfa46f580bcb1a5ec724
Bug-Url: https://bugzilla.redhat.com/1020858
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>