Update git submodules

* Update docs/submodules/fuel from branch 'stable/fraser'
  - Unmask OpenDaylight service explicitly

    After salt update to version 2017.7.0 the indefinite mask
    has to be removed before attempting to start the service.

    Change-Id: I21616929f06f8ebd8a2d70e8c33f92c7b808a9c5
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>
    (cherry picked from commit 941a31e1e7f64f38a487b4e493bc25fdf29657da)

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index efec10f..8eff52b 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit efec10f8e81336b101a931f0195493d863858302
+Subproject commit 8eff52b0d776a278ca031feb35c0bb2bc0ebfebe