Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Conform constants.py with the minimal standards"
  - Conform constants.py with the minimal standards

    It adds the shebang to constants.py and its dependencies and stops
    importing from a relative path. It stops printing obsolete values too.

    It adds python3 support to them by the way.

    Change-Id: Ie7bddcf253eb245844d9e11c17acc69943c1ba63
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>