Update git submodules

Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Merge "Refactor unit tests in 'test_odl_utils.py'"
  - Refactor unit tests in 'test_odl_utils.py'

    JIRA: SFC-126
    JIRA: SFC-129

    Some of the unit tests I wrote earlier needs to be separated into
    individual unit tests, which Mr Dimitrios has mentioned in one of
    my previous commits. Unit tests are supposed to be independent &
    should only test one test case at a time. This patch fixes them.

    Change-Id: Iaf20e5868491f0627882929a953f3c4a3273f626
    Signed-off-by: Venkata Harshavardhan Reddy Allu <venkataharshavardhan_ven@srmuniv.edu.in>