Various

1.  Renamed IGridGenerator to IGridBuilder.  Updated unit test names
accordingly.
2.  Renamed GridProvider to GridPainter.
3.  Renamed method DrawGrid to PaintGrid, re class GridPainter.
4.  Renamed GridBuilder to EmptyGridbuilder.
5.  Renamed GridManager to GridControlBuilder
6.  Renamed Unit test classes accordingly.
7.  Unit test class added for GridPainter and started.
8.  UnitTest class added for GridControlBuilder
9.  Added interface IGridControlBuilder and GridControlBuilder deriving
from
10.  Injected interface IGridControlBuilder into GridPainter and
implemented