title: Force TextField with type number to display dot as decimal separator
body: <p>I am using <code>material-ui</code> to render a <code>TextField</code> component in my <code>react</code> app. It's somehow forcing all the <code>&lt;TextField type="number /&gt;</code> to have decimal separator as comma (,) instead of dot (.) which is confusing for the targeted users.  </p>
  
  <p>Is there any way to force it to always show dot as the decimal separator, regardless of locale? </p>
  
  <p>I have created a <a href="https://codesandbox.io/s/material-demo-hsj2l" rel="noreferrer">small example here</a>. just try to enter a number with decimals and click outside and it'll convert it into comma. This is probably because of my current device locale, but still I want to force a dot for everyone.</p>