Update git submodules

* Update docs/submodules/sdnvpn from branch 'stable/euphrates'
  - Merge "Adding scenario documentation" into stable/euphrates
  - Adding scenario documentation

    Adding the scenario documentation, which was missing from previous commit.

    JIRA: SDNVPN-185

    Change-Id: I5b4f79f51ecd50a2bc514ca0e845679604716143
    Signed-off-by: Tim Irnich <tim.irnich@ericsson.com>
    (cherry picked from commit 66f4fcfc64ed884b5adb2e78447b44ec0639fc6c)

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index d7bd8e9..e9ade96 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit d7bd8e9750d6dac28a71a7954795101ee0dd2896
+Subproject commit e9ade965ab40c3321b4aab03104e7e211af73d0a