#5 Support for several drawings inside one control

[Mikhail Vladimirov]

Implement the following abilities:

1. Display several drawings (several data models) inside
one JDrawing control

2. Use different origin points for different drawings

4. Use different element renderers for different drawings

5. Use different model caches for different drawings

6. Draw something between drawings (now it is possible
to draw something before and after the drawing)