Update git submodules

Update git submodules

* Update docs/submodules/multicloud/k8s.git from branch 'master'
  to c257a136355a794f5bf778f670c041e8958c3608
  - Adding cluster meta data and saving in etcd

    As part of this patch, we assign groupNumbers
    for the set of clusters which are under anyOf, or
    in other words are optional for deployement of
    app.
    Also refactored the instantiation flow by separating
    out the etcd interactions

    Issue-ID: MULTICLOUD-1064
    Signed-off-by: Rajamohan Raj <rajamohan.raj@intel.com>
    Change-Id: I21ece189daf6e6b3a7cfdba5df22d57b3d33ca78