Update git submodules

Update git submodules

* Update docs/submodules/vswitchperf from branch 'stable/danube'
  - Updates release note numbering

    Change-Id: Id0510b96375033540fa80fe22b301fb1d0d20e40
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
    (cherry picked from commit bc150a3ea5ac7729747e16bb093c37101e2b803c)

  - Updated results and sceanrios for Danube

    Change-Id: I3f29b4e9431a98d65f363273bed57f96d6e993ca
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Updates for new doc structure

    Change-Id: Idc496e246f966f2882ce0c439913c9379b31c5ea
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - New doc structure changes for stable/danube

    Change-Id: I2e9b432a74ee22690fdb366de619dc3a5d2ad725
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Moved results to developer dir

    Change-Id: I7d2d5939e018c7abae03663b13be8f8f038256c0
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Moved requirements to developer dir

    Change-Id: I2fa9e32d4ae92aa1f075c1da8e2acb3912f3f7bc
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Moved design to developer dir

    Change-Id: I487619deca2658d5239cccd41098751cc8245b34
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Moved userguide to user directory

    Change-Id: I35f2cbbab8ce7daec26fed63fa92cf7c17cd37b3
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Moved configguide to user dir

    Change-Id: I13b6b2cb184d864f41ecfe9478c02bfc8257fff3
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Updated release notes index file

    Change-Id: I68e1eb9313ebca753f31094137d7d50a24e33c69
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
  - Renamed release notes file and added index file to release-notes dir

    Change-Id: I448fd909a89103b2c11cb16f91b8c646fb5adee8
    Signed-off-by: Trevor Cooper <trevor.cooper@intel.com>
    (cherry picked from commit 59668b1aa68da507335ef351619d9f50019df762)

  - Fix fuel plugin installation issue in latest ISO

    Change-Id: I8383b469f5350f4457cf234de2a4ff8f79151afe
    Signed-off-by: Guo Ruijing <ruijing.guo@intel.com>