Update git submodules

Update git submodules

* Update docs/submodules/vid.git from branch 'master'
  to 81c3ee59ef8196cc349bcff46f9e14a08bb16ec6
  - Configure c3p0 liveness check of ext-svc-simulator

    Check the viability of ongoing connections quite rapidly, allow
    stable log-ins while tests.

    "Your application should experience broken or stale Connections only very rarely"
     - https://www.mchange.com/projects/c3p0/#simple_advice_on_connection_testing

    Issue-ID: VID-647

    Change-Id: If5f3683a781c2c3bccb7b118ec96205000ee4547
    Signed-off-by: Ittay Stern <ittay.stern@att.com>