Adds support for cf-core and updates OS info.

Oops, looks like cf-core has been adding duplicate styles into components because of its unique use of `@import` statements. This updates the concat task to ignore all Less files in cf-core except for `cf-core.less`. The ignored files will be imported through `cf-core.less`'s `@import`s. It also removes the need to concatenate the Normalize files during the Less compile task.

This also fixes sourcemaps, but they still only work for local testing since we aren't committing vendor files. And it's still not perfect because we're concatenating CF components into cf-concat, which means that if your component depends on cf-buttons you'll only see it in `cf-concat.less` not `cf-buttons.less`.