Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "Install docker and shade on opnfv host"
  - Install docker and shade on opnfv host

    Docker is needed for running tests against the deployment.
    Shade is needed for managing OpenStack via Ansible.

    This change adds tasks to install docker and shade on opnfv
    host if it is run as part of CI.

    Users should be free to install these if they want so it is
    not installed for them by default.

    Change-Id: Idfd0f02312cc5e1b0180ed2408755a8c730b987b
    Signed-off-by: Fatih Degirmenci <fatih.degirmenci@ericsson.com>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index bb7e7ef..50c132f 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit bb7e7efef45d8347c08022c7246d6111887b864d
+Subproject commit 50c132fa9d563f6a4d81938814937da2dfa957ca