Update git submodules

Update git submodules

* Update docs/submodules/dovetail from branch 'master'
  - Transfer Danube reviewer guidelines from wiki

    The reviewer guidelines will be created per release, where the
    CVP/Dovetail releases are aligned to OPNFV releases. The guidelines
    outlined in this initial document are for the Danube release.

    Updated reviewer guidelines

    - Updated to account for issue where mandatory total always shows 215
    in current version of web portal; removed one diagram and amended another
    - First section title change and wording for test area results

    - Removed white space
    - Added SUT info section and diagrams
    - Modified reference to cvp.opnfv.org with verified.opnfv.org
    - Modified reference to cvp@opnfv.org with verified@opnfv.org
    - Modified diagram filenames to reflect program name change
    - Changed CVP references to OVP and Danube to 2018.01
    - Remove TODO for granting marks and escalation - this info is in other docs

    Change-Id: I01fc568ce6713d3c60daf339a2630e56e8dbcfcb
    Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>