Implement response curve action

[WhiteMagic]

Implementation of the response curve UI, i.e. the curve aspect as well as the deadzone. The entire curve rendering aspect needs to be redone as QML handles this differently.

Functionality that needs to be supported:

• Dragging of control points and their handles (if used)
• Numerical input of control point and handle coordinates
• Support for symmetry and smoothness constraints
• Ability to invert a curve

Possible nice to have features:

• Toggle for live feedback of a curve

[WhiteMagic]

Include the resolution of #428 as well to ensure the UI is flexible enough to handle various curve types.