Spinner implementation #120

[gabbsmo]

Spinner implementation based on styles from Fluent React, but adopted to fit into htwoo's convention.

[StfBauer]

Don't put all the spinner in just one file. This avoid's to get reused - Instead use variations of the spinner like:
https://patternlab.io/docs/using-pseudo-patterns/

Also the default verison is missing.

[gabbsmo]

Gave it a try. I am completely new to Pattern Lab.

Default and Medium is equivalent. Can remove one of them, whichever you prefer.

[StfBauer]

Just show the default one. Add a markdown that it equals the medium spinner.

One thing we could do in case of the spinner have something like this:

.hoo-spinner{
    
    &.xsmall{
    }

    &.small{
    }
    
     &.large{
    }
    
}

So default spinner with modifier classes.

[gabbsmo]

Actually, I think I tried modifier classes at first but found that .medium collided with some other already existing style. Because of that I went with the appoarch in the PR. It also seemed to be more in line with other styles such as .hoo-button, .hoo-button-primary, rather than .hoo-button.primary.

But if you prefer the style in your example we can go with that of course.