Update git submodules

Update git submodules

* Update docs/submodules/apex from branch 'master'
  - Merge "Promote Ricky to committer"
  - Promote Ricky to committer

    Ricky has been a very active Apex user and contributor over the past few
    release cycles.  He has helped find and fix numerous bugs, along with
    being responsible for L2GW and SRIOV features for Fraser release.  He
    has shown a willingness to jump in and help whenever there are issues
    with Apex, and also a willingness to work upstream in TripleO/OpenStack
    to implement new features.

    Change-Id: Ifd032fd349a46b0e34b2d77ba56e3c564e70226c
    Signed-off-by: Tim Rozet <trozet@redhat.com>