Bug 496890 - Update o.e.help.ui to Java 8

Enable missing Override warning and fix them by using one of the
following approaches:
* Listener -> Adapter to remove empty methods.
* Convert to lambdas.
* Add the annotation.

Change-Id: Ie597574da8ecfdc09db34e3421ff89cb2d57917d
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>
80 files changed