Clean up Maven dependencies (part 1)

Clean up Maven dependencies (part 1)

Remove unused dependencies, and explicitly declare dependencies
which are used directly (and used to be pulled in transitively).
This will help future work on odlparent and upgrading upstream
dependencies, as well as stabilising the dependencies on other
ODL projects.

The changes necessary were determined using
dependency:analyze-report.

Change-Id: Ie3ac0a6e4a98c69e253b9c851e7b0d5dc5f3ded8
Signed-off-by: Stephen Kitt <skitt@redhat.com>