webadmin: VM dialog Host tab for Local SD

In vm/template/pool dialog Host tab will be visible for
local SD data center (to show other host fields, used to be hidden).
In local DC Migration fields will be disabled and set to
non-migratable and pinned.

Change-Id: I490f19a9a66c78d9f0d81bf5fb009d2a8eec38a4
Bug-Url: https://bugzilla.redhat.com/1018201
Signed-off-by: Gilad Chaplik <gchaplik@redhat.com>