Update git submodules

* Update docs/submodules/qtip from branch 'master'
  - Merge "revert the usage of qgrid since it is not supported by nbviewer"
  - revert the usage of qgrid since it is not supported by nbviewer

    Change-Id: I870bc80064fa202beab6e4715e4f197826bee8c2
    Signed-off-by: Yujun Zhang <zhang.yujunz@zte.com.cn>

diff --git a/docs/submodules/qtip b/docs/submodules/qtip
index 06b4f38..84bc907 160000 (submodule)
--- a/docs/submodules/qtip
+++ b/docs/submodules/qtip
@@ -1 +1 @@
-Subproject commit 06b4f3801918ff5548b25e3897a49fe3e3953d9a
+Subproject commit 84bc90765fdee6271d23f0ae41a04489c164f348