Update git submodules

Update git submodules

* Update docs/submodules/oom/offline-installer.git from branch 'master'
  to 37796bfe9db3f947429b325f86450bfc9512ed9a
  - Merge "Add docker local registry cleaning script"
  - Add docker local registry cleaning script

    Since with changing data lists there are unused images
    left in local registry on build server this
    commit adds script that handles that.

    Issue-ID: OOM-1952

    Change-Id: Ied7a8b09aacd33ef17f0676cfab333d1df8a1a81
    Signed-off-by: Milan Verespej <m.verespej@partner.samsung.com>