Gradient bar and fill color

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Checklist

• I'm using 0.4.7 [x.x.x]
• My chrome and firefox is:
• This is a Sass issue: I'm using version [x.x.x]
• I am sure this issue is not a duplicate?

Description

Can you please add gradient option for fill color and bar color?

For example: https://www.jqueryscript.net/demo/Animated-Circular-Progress-Bar-with-jQuery-Canvas-Circle-Progress/