Progress Indicator

[cindyebi]

Following up the previous discussion about new components, I thought it's better to separate them into different threads.

### VF-Progress-Indicator
Initially, this component was created to address the need of the Training Academy's personal space project where users could track their learning progress by creating an account. The following mockups show different states and ways of labeling.

Mockups:
v1: word-done progress indicator

v2: percent-done progress indicator

Some thoughts:

• At the moment, the purpose of this component is meant to show progress indicators only (users can't interact with it), not to be confused with a progress tracker, though Carbon Design uses the "Progress Indicator" naming convention to show step-by-step progress. I think it will be helpful to clarify the scope of the definition and implementation of this component at this stage.
• NNGroup specifically called this component a "Percent-done animation progress indicator" that should be used for longer processes that took more than 10seconds.
• Material Design defines Progress Indicator similar to a spinner or loader component but visualized differently.

[cindyebi]

@khawkins98 @nitinja shall we group the spinner loader and this progress bar under "vf-progress-indicator"?

[nitinja]

I think that the plan already?

[nitinja]

started on this component, thanks