Update git submodules

* Update docs/submodules/yardstick from branch 'stable/fraser'
  - Merge "Replace nova get server with shade client." into stable/fraser
  - Replace nova get server with shade client.

    Rename get_server_by_name with get_server.
    Function get_server now uses shade client.

    JIRA: YARDSTICK-1088

    Change-Id: I69c59145cefdb565f3ece27baaaf932905e1b757
    Signed-off-by: Shobhi Jain <shobhi.jain@intel.com>
    (cherry picked from commit d75a91ebf2937e5cfe5cf2aa5a90db9121f73967)

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index e8a0b1b..ecade87 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit e8a0b1b9662e323499de66aaf3800750f51c1299
+Subproject commit ecade87f9b6b10c2c13ae42d78b82e0792a31ffe