[feature request] second button for generating gcode.

[legend069]

Is your feature request related to a problem? Please describe.
on low performance pc's it can be time consuming having to wait for the gcode generation to complete, when you just want to slice a model to see if it needs supports in areas

Describe the solution you'd like
config preference to enable/disable this feature

Describe how it would work
if generate gcode enabled when user clicks on "slice" it will slice model and generate gcode.
if generate gcode disabled when user clicks on "slice" it will slice model and not generate gcode till use clicks again for generate gcode.

[Tinchus2009]

Actually I think it can be more simple: just disable default gcode generation after theh slice, and just generate the gcode when the user press "export gcode"