Add mockito-configuration to tests

Add mockito-configuration to tests

Ynagtools' mockito-configuration ensures that all methods touched in
mocked objects have to be mocked, preventing failures which are hard to
track down.

The reason for this is that by default unmocked methods do nothong and
return null -- injecting nulls into context which do not expect them.

Change-Id: If7b9afac01128be6f1b2a90b1e8c068cb4a39b65
Signed-off-by: Robert Varga <robert.varga@pantheon.sk>