[Docs] Add info about 2.2.0 version of execution plan template format
[Docs] Add info about 2.2.0 version of execution plan template format

Since commit I036b5b9b7e1202d26fa2fd16591b680755cbfbc1 the minor version
was incremented and Berkshelf support was added

Change-Id: I28da993f040c96cde123c3c79d04a246f9ad71e2

DavidPurcell/murano_temp,DavidPurcell/murano_temp,DavidPurcell/murano_temp,openstack/murano,openstack/murano,DavidPurcell/murano_temp