Add a spinner while loading

[Wulfheart]

A visual clue would be helpful while livewire is doing something in the background.

I recommend the tailwind spinner plugin for this purpose.
I'd be willed to create a PR if any of the maintainers (I assume @imliam and @danharrin) approve the usage of an additional tailwind plugin.

[danharrin]

Hey, I'd rather reduce the number of unofficial dependencies really? I reckon we could get away with a loading class on the buttons -

wire:loading.class="opacity-75 cursor-wait"

This works a treat normally.

[Wulfheart]

@danharrin Ok. Will make it. 😎

[stefanfisk]

Since Tailwind now supports animations, this could be implemented without adding a dependency: https://tailwindcss.com/docs/animation#spin.