Now the os-migrateLive API supports a new body argument called 'force' which
helps the operators to bypass the scheduler call in case they provide a host.
Also modifies the host_evacuate_live helper method in the contrib tree to make
sure operators also have the force flag in case they need it for a global call.
Change-Id: Id7fcd88ad060390ac6d1a21510d84363ed643957
Implements: blueprint check-destination-on-migrations-newton
c649678991