Update git submodules

* Update docs/submodules/sdnvpn from branch 'master'
  - Fix error on querying neutron quota

    JIRA: SDNVPN-233

    This patch fixes the bug which exists when trying to query neutron
    quota with openstacksdk.

    Change-Id: Iead824ca44f381ba314f38933cf48fe7932f74f3
    Signed-off-by: Stamatis Katsaounis <mokats@intracom-telecom.com>
    (cherry picked from commit 7e52a1809501699a6da9fda5c2613a76abe384d3)

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index 9a70aca..edd6cfe 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit 9a70acabe83d10fd1ac1b0de5b7ce480929b55e7
+Subproject commit edd6cfe15ecd4e2bf608c23c6ca4612334df044b