Implementation of outline button

[dilipkumar2k6]

As per material ui design, outline button is accepted design. However I don't find code in material-ui. Please refer https://material.io/design/components/buttons.html#usage

• [x ] I have searched the issues of this repository and believe that this is not a duplicate.

Expected Behavior

I should be able to use varien="outline" as below
<Button variant="outline" color="primary" className={classes.button}> Primary</Button>

Current Behavior

Not able to find in document on how to use outline button.

Steps to Reproduce (for bugs)

Context

My designer designed outline button and I do not want to write lot of stylesheet to create my own version.

Your Environment

Tech	Version
Material-UI
React
browser

[oliviertassinari]

@dilipkumar2k6 Thanks for raising this point. I'm closing for #11284.