Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to d37a45ab352084738b3f95cb64cc83d4e1484d0b
  - Add additional error messages to dmaap service

    Add error checking and logging if required properties
    are not present.

    Change-Id: I270a7a088e36de603b89133e9ccb22f206e931e4
    Signed-off-by: Patrick Brady <patrick.brady@att.com>
    Issue-ID: APPC-1744

diff --git a/docs/submodules/appc.git b/docs/submodules/appc.git
index 08a64bd..d37a45a 160000 (submodule)
--- a/docs/submodules/appc.git
+++ b/docs/submodules/appc.git
@@ -1 +1 @@
-Subproject commit 08a64bdc7db020e4e928f194ed8dd0059627b1aa
+Subproject commit d37a45ab352084738b3f95cb64cc83d4e1484d0b