Update git submodules

Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to 7b04a1754482ba02a49d4d6376dc45e4cd6551f4
  - Cleanup of dmaap adapter

    Remvoing the part of the appc-dmaap-adapter that uses
    the dmaapClient library. This part of the code was not
    being used and the dmaap client library has not been
    updated for a long time. Also removed several un-used
    dependencies.

    Change-Id: I690afaecbfe53d88576c43aa8d114fde54c0fe48
    Signed-off-by: Patrick Brady <patrick.brady@att.com>
    Issue-ID: APPC-1744