Update git submodules

Update git submodules

* Update docs/submodules/samplevnf from branch 'master'
  - Added initial draft for samplevnf useguide

    JIRA: SAMPLEVNF-77
    Change-Id: Ib537b36ae82361754762a627ae942d99b4966856
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>
  - Update vACL config files

    JIRA: SAMPLEVNF-76
    Change-Id: Iab363cc6cd5310e25c15758f02ca68751e81a49c
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>
  - Updated configuration files for cgnapt VNFs

    JIRA: SAMPLEVNF-75
    Change-Id: Iac091ca0f12570d47d36366055ad89737b386c36
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>
  - Update vCGNAPT configuration file

    JIRA: SAMPLEVNF-75

    Change-Id: Icb8e46ee4566cc637b299913b1d0a7d5baafd3ac
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>
  - Adding Initial samplevnf release notes draft for E-Release

    JIRA: SAMPLEVNF-74
    Change-Id: I6d3adacc9236006f64218aad5378a4af5dd2efe5
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>
  - Remove unwanted files in docs folder

    JIRA: SAMPLEVNF-73

    Change-Id: Ia147cfef9f7bcacd50477b6ea3c7d0a1c6e93952
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>