Run clang-tidy modernize-use-override to remove all the redundant
virtual keywords from overridden methods, and add some missing
overrides.
Another benefit is that this has also added the overrides
on destructors, which will cause a build failure if a base
class is missing a virtual destructor.
This adds a new interactive "curve" to the assistant widgets.
It allows you to fine tune exactly how input values get
mapped to output sizes/colors/etc.
Think GIMP or Photoshop curves, but for your data...
