Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [docs] Updates for the first Fraser release

    Change-Id: I80dfb55c01af89bded1140cd27563d258e05dda4
    Signed-off-by: Cristina Pauna <cristina.pauna@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 71639a2..b67b07e 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 71639a2c6da028aa98b5e324ddeb650ebfb4ead6
+Subproject commit b67b07e5654dbe0c7524e47ebb97eed987edf3d6