Add ability to resize "Add Automation" panel

[sgoff]

Currently, the Add Automation panel is a fixed size when opened. Allowing the panel to be resized would enable the possibility of drawing more detailed or complex automations.

If such a feature were implemented, the stroke width of the dashed automation line segments (and the size of segment endpoint dots) should not be scaled larger or smaller as the panel window is resized. They should stay the same size, while the locations of any endpoints defining drawn automation, within the panel, should scale with the panel size.