Add view options to the gradient chooser (4.3)

This MR adds view options to the KisGradientChooser (used in the toolbar gradient button).

When making the KisGenericGradientEditor I used a KisResourceItemChooser and added to it view options. Then @tymond pointed out to me this bug 425929 (I think that was it) and suggested that I put the view options in the other places.

So I copied the view options to the KisGradientChooser and made the KisGenericGradientEditor use it directly instead of using the KoResourceItemChooser.

I added some code to allow the chooser to share the options with other choosers if they are set to use the global view options (a gradient chooser can be used now in global mode, sharing the view options, or standalone with its own view options).

Formalities Checklist

• I confirmed this builds.
• I confirmed Krita ran and the relevant functions work.
• I tested the relevant unit tests and can confirm they are not broken. (If not possible, don't hesitate to ask for help!)
• I made sure my commits build individually and have good descriptions as per KDE guidelines.
• I made sure my code conforms to the standards set in the HACKING file.
• I can confirm the code is licensed and attributed appropriately, and that unattributed code is mine, as per KDE Licensing Policy.