[Feature] Add `switch` field to `backpack/pro`

I think we should move the toggle field type from a separate package… to the backpack/pro repo. But if we’re doing that, it’ll be a good time to also make the colors and stuff easy-to-customize, like @promatik did on the corresponding “editable column”.

[tabacitu]

Hmm you’re right @rroblik … once it’s free… we can’t really make it un-free. Don’t know how I missed that. So the free toggle package stays there, no way for us to close-source it at think point. Thanks for the observation.

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Ok then… but I still want a supercharged field that does that. I want to be able to add switches to my admin panel instead of checkboxes, because that alone will make the form prettier, I think. And I want them to be customizable, to support as many variations as possible from what we offer in Backstrap:

• MUST: easily change color;
• SHOULD: easily choose the text on the switch (eg. ON / OFF);
• SHOULD: easily choose an icon to show on the switch (eg. la la-warning);
• SHOULD: easily make it small / medium / large;
• COULD: easily change style (3d / 2d / square);
• COULD: easily make it outline (so it doesn’t stand out as much);

So here’s what we can do:

• keep the digitallyhappy/toggle-field-for-backpack as it is; free and open-source;
• create a new field for backpack/pro, that we call switch;

Then people can use whatever they want, either the free toggle or the premium switch. People who use Backpack\CRUD have to install this additional package, which adds it but is not-so-feature-packed. People who use Backpack\PRO have it at hand always, and it’s feature-packed. Everybody wins.

[promatik]

This feature is now at https://github.com/Laravel-Backpack/CRUD/pull/4463 🎉