feat(component): Add loading indicator

[riccardo-vettore]

What is it?

• Feature / enhancement
• Bug
• Docs / tests

Description

Add new loading indicator component

Use cases

<LoadingIndicator
      style="font-size: 3rem"
      width="10px"
      indicatorColor="darkblue"
      trackColor="lightblue"
      speed="4s"
></LoadingIndicator>

Screenshots/Demo

[gioboa]

I'm thinking if loading-indicator is the right name.
I checked angular material and they call this component spinner https://material.angular.io/components/progress-spinner/overview
What do you think about this?

[riccardo-vettore]

Yes, I agree, this component should be called spinner.

[gilf]

Yes, I agree, this component should be called spinner.

Agree with @gioboa. The component should be called Spinner. Once you change the name, we will merge it :)

[gioboa]

Great work. Thanks

[gioboa]

Closes #133