ISTWCMS-5593: inital import of uw layouts and grid

src/patterns/01-core/mixins/_index.scss

src/patterns/01-core/mixins/_uw-mixins.scss

src/patterns/01-core/props/_layout.scss

src/patterns/01-core/props/_media.scss

src/patterns/02-base/colors/colors.twig

src/patterns/03-layouts/grid/_grid.scss

src/patterns/03-layouts/grid/grid.twig

src/patterns/03-layouts/grid/grid.yml

src/patterns/03-layouts/grid/grid~2col.yml

src/patterns/03-layouts/grid/grid~3col.yml

src/patterns/03-layouts/grid/grid~4col.yml

src/patterns/03-layouts/grid/grid~6col.yml

src/patterns/03-layouts/layout/_layout-base.scss

src/patterns/03-layouts/layout/_layout.scss

src/patterns/03-layouts/layout/_layout.twig

...terns/03-layouts/layout/layout--1-col/_layout--1-col.scss

...tterns/03-layouts/layout/layout--1-col/layout--1-col.twig

...atterns/03-layouts/layout/layout--1-col/layout--1-col.yml

...terns/03-layouts/layout/layout--2-col/_layout--2-col.scss

...tterns/03-layouts/layout/layout--2-col/layout--2-col.twig