Update git submodules

Update git submodules

* Update docs/submodules/odlparent from branch 'master'
  to 8c1daff6db22606b614348a6574d0f6834809dc2
  - Add odl-jackson-2.8

    This a package containing a pre-configured jackson software package.

    Change-Id: I459cfda5fb147b21a1e5339360fac06522307fbc
    Signed-off-by: Robert Varga <robert.varga@pantheon.tech>
  - Bump akka to 2.5.10

    https://akka.io/blog/news/2018/02/23/akka-2.5.10-released

    Change-Id: I10d598a96e4a08078e10551517cee7f3882fc49d
    Signed-off-by: Robert Varga <robert.varga@pantheon.tech>