Update git submodules

Update git submodules

* Update docs/submodules/ccsdk/platform/plugins.git from branch 'master'
  to 85b8365c69b25191ba53390ba8ae9c7ad8e9f18b
  - PGaaS plugin -- modify code to support python3

    add code to work on both python2 and python3
    lots of pylinting
    remove debug logging of a password
    improve error message when given an invalid cluster name, simplify some code
    password changing capability for a database
    tox tests improvements
    NOTE . . .
    The PGaaS plugin uses several Cloudify mock libraries, one of which
    is not compatible with Python3.
    Until we get an updated version of that Cloudify mock libraries,
    we will have to leave out py3X from the tox tests.
    We cannot use py37 yet because Jenkins returns:
    InterpreterNotFound: python3.7
    So tox.ini is using envlist = py27

    Change-Id: I795b71cc8a1fdea043e2ff3a0d66bb95e3f93a89
    Signed-off-by: Hansen, Tony (th1395) <th1395@att.com>
    Issue: CCSDK-1599
    Signed-off-by: Hansen, Tony (th1395) <th1395@att.com>