Update git submodules

* Update docs/submodules/externalapi/nbi.git from branch 'master'
  to 540ea00963f4bf7ad01819b9263a425db68e628e
  - Add _static files for docs

    .gitignore was preventing these files from being
    added. Update to not ignore the files and re-add
    them in docs folder

    Issue-ID: CIMAN-33
    Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
    Change-Id: Ic32d3526f32b6feb1adf7f1a1e5f90df36659a40

diff --git a/docs/submodules/externalapi/nbi.git b/docs/submodules/externalapi/nbi.git
index 484aa93..540ea00 160000 (submodule)
--- a/docs/submodules/externalapi/nbi.git
+++ b/docs/submodules/externalapi/nbi.git
@@ -1 +1 @@
-Subproject commit 484aa93ab7d9364c2d75cce2b017323f62d397d9
+Subproject commit 540ea00963f4bf7ad01819b9263a425db68e628e