[DIC]: \SMW\JobBase implements \SMW\DependencyRequestor

\SMW\UpdateDispatcherJob
Code coverage: 100%
CRAP: 15

\SMW\UpdateJob
Code coverage: 100%
CRAP: 9

\SMW\UpdateObserver
Code coverage: 100%
CRAP: 5 (before 15)

+ Cleaner interface
+ Eliminate setter/getter clutter

Change-Id: I3e9ee616b2d3667032c6bd3be6c3f88eca4017be