Bug 449764 - moved logic to redraw leftover space to NatTable
Bug 447133 - corrected usage of stepCount on traversal cycling
Bug 450548 - change method signature of registerOverrides(int, String[]) to registerRowOverrides(int, String[]) to remove compiler errors for ambiguous method signatures
Bug 447133 - extended ITraversalStrategy and corresponding handling to be able to specify valid move targets, e.g. EditTraversalStrategy which will jump to the next editable cell in case the selection movement is called on editing