Rois from new api

[will-moore]

See https://trello.com/c/wUy0dwO8/58-figure-roi-loading

This updates OMERO.figure to use the new JSON API to load shapes: /api/v0/m/rois/?image=1.

To test:

• Add ROIs to panel, including Rectangle, Line, Arrow, Ellipse.
• Crop panel using Rectangles saved on the image.

--exclude