Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Switch off broken sphinx state

    Deactivate documentation related optional state
    until it get fixed in upstream.

    Change-Id: I5242ed307548c4f37f81d271a1f4f6bee9903f4e
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 624e0e3..854729d 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 624e0e31debf1b4f7fa7727826e6e385c6192583
+Subproject commit 854729dd3174985f524c2a2ab9d373b65f49d188