Update git submodules

* Update docs/submodules/nfvbench from branch 'stable/euphrates'
  - Add dev section to doc

    Change-Id: I1e8d4a3fa6be7305c89fbc28b31377ec0f9d51a2
    Signed-off-by: ahothan <ahothan@cisco.com>

diff --git a/docs/submodules/nfvbench b/docs/submodules/nfvbench
index 152d3f4..b01bb43 160000 (submodule)
--- a/docs/submodules/nfvbench
+++ b/docs/submodules/nfvbench
@@ -1 +1 @@
-Subproject commit 152d3f49f8208adc1d0b37d41356163ca65fe0ca
+Subproject commit b01bb43efe2e65d89d2a0488c87126af03a606e1