Update git submodules

* Update docs/submodules/policy/engine.git from branch 'master'
  to c7ebafd4e235416090ddcea8eadc37ffad53bdc9
  - Merge "Change AlertSeverity to Severity in policy/engine"
  - Change AlertSeverity to Severity in policy/engine

    Updated logback xml files, replacing AlertSeverity with Severity.
    Also fixed some spacing issues.

    Change-Id: I3e4b9163d5d897fe4402028b69c741f497aecfc5
    Issue-ID: POLICY-1989
    Signed-off-by: Jim Hahn <jrh3@att.com>

diff --git a/docs/submodules/policy/engine.git b/docs/submodules/policy/engine.git
index 9039e5d..c7ebafd 160000 (submodule)
--- a/docs/submodules/policy/engine.git
+++ b/docs/submodules/policy/engine.git
@@ -1 +1 @@
-Subproject commit 9039e5dacc397fdf94aa19cac1f5531d7661cb03
+Subproject commit c7ebafd4e235416090ddcea8eadc37ffad53bdc9