Feature request - custom tool change gcode

[whosawhatsis]

For multi-extruder printing, it would be very useful to have a section in the custom gcode pane for custom gcode surrounding a tool change. It would be nice to be able to add code both before the tool change (for instance, partially cool the extruder that is no longer being used to reduce ooze) and after (re-heat the new extruder). This could be accomplished with two boxes for custom gcode, or with one with an option to add a token like "%T" to specify where in the code the toolchange should appear.

[alranel]

Duplicate of #547

[Deezmaker]

I concur. This would be extremely useful and flexible with multiple extruders on any printer.