Add KeyName to Instance heat template
Add KeyName to Instance heat template

Adds an ssh keyname if specified to the Heat template; it is optional
and defaults to null.

Change-Id: Id80cf403f834a9ed8d3a0660a2687ab17ddb0f6d

satish-avninetworks/murano,sajuptpm/murano,olivierlemasle/murano,satish-avninetworks/murano,DavidPurcell/murano_temp,NeCTAR-RC/murano,NeCTAR-RC/murano,sergmelikyan/murano,DavidPurcell/murano_temp,satish-avninetworks/murano,chenyujie/hybrid-murano,DavidPurcell/murano_temp,openstack/murano,olivierlemasle/murano,olivierlemasle/murano,sajuptpm/murano,ativelkov/murano-api,ativelkov/murano-api,olivierlemasle/murano,telefonicaid/murano,satish-avninetworks/murano,sergmelikyan/murano,telefonicaid/murano,DavidPurcell/murano_temp,NeCTAR-RC/murano,chenyujie/hybrid-murano,openstack/murano,NeCTAR-RC/murano