Text boxes

[Cullen-Enerdyne]

Keeping this separate from #325.
We need textboxes that do the following:

• Contain text
• Have options for coloured backgrounds, borders
• Allow some text formatting (multi-line text, different text sizes, colours, typefaces etc.)
• Control the region text is limited to, or how the text expands when more text is added (basically text overflow control)
• Be movable and resizable (not necessarily resizing text at the same time)

-Text boxes should have a reserved layer (with #54 ), behind text, but in front of all other primitives. (I think this is a logical design decision, as text should always be visible)