Add 'host' parameter to wadl of the api v2/{tenant_id}/servers

For the api v2/{tenant_id}/servers, the wadl is
    api-ref/src/wadls/compute-api/src/os-compute-2.wadl, no change.
Put 'host' into the parameter list which is in
    api-ref/src/wadls/compute-api/src/common.ent

Story 130902
Epic 129324

Change-Id: I81250e0c5c6820cf9fb9dfa1c043c668c9e1da2b