Provide collection/index controls in display panel

[cmeyer]

Also will reorganize how adornments such as source/dependency items, collection/sequence/item pickers, and the scale marker are laid out.

• The scale marker overlaps and needs to participate in the layout, but only for raster
• The index slider overlaps the line plot and needs to reserve space, but only for line plot
• Update the index, etc. through a window action instead of direct modification, undo
• The sequence, collection index needs to display values in calibrated coordinates
• Add a slice control also