Clean copy of EditCanvas. [1765]
Should be the last override...

Well, the last override for [1765]. :(
Replace JColorChoosers in Station Model editing.

[1765]
Replace JColorChooser in Display Settings. [1765]

This should be the last one that needs to be replaced. There are two
remaining spots where JColorChooser is used (but I believe to be
legitimate).

* ColorTableCanvas.java: the JColorChooser is used more as a base upon
which the color table editor is built.

* GuiUtils.java: the old ColorSwatch widget uses a JColorChooser. The
code is marked as deprecated since removing it could introduce problems
with plugins and whatnot.