Update git submodules

* Update docs/submodules/odlparent from branch 'master'
  to 93b18bf5416688b3d5bffecc3e688fe5a671217f
  - Update usage information for odlparent properties

    This patch updates the usage information for all active projects in
    ODL, and removes some unused properties:
    * maven.clean.plugin.version
    * compiler.version
    * releaseplugin.version
    * akka.version
    * leveldb.version

    This is technically a breaking change, so this is 4.0 material only.

    Change-Id: Ia68136adef7c6ab3c40544546908653e81d8ba11
    Signed-off-by: Stephen Kitt <skitt@redhat.com>

diff --git a/docs/submodules/odlparent b/docs/submodules/odlparent
index 7f56e62cf7e36c5fffddf34fe38fadae9bed5323..93b18bf5416688b3d5bffecc3e688fe5a671217f 160000 (submodule)
--- a/docs/submodules/odlparent
+++ b/docs/submodules/odlparent
@@ -1 +1 @@
-Subproject commit 7f56e62cf7e36c5fffddf34fe38fadae9bed5323
+Subproject commit 93b18bf5416688b3d5bffecc3e688fe5a671217f