Adding extra breakpoints trough gridThemeProvider

[subodha]

This is awesome. However I found 2 issues regarding breakpoint

1. xs and xxl breakpoints are not adding to generate css
2. when I tried to add extra breakpoints they are now adding to generated css.

const gridTheme = { gridColumns: 12 breakpoints: { xxxl: 1920, xxl: 1440, xl: 1200, lg: 992, md: 768, sm: 640, xs: 575, }, }

it is great if we can get this fixed.

Thanks

[rakeshmenon]

Same issue for me.