Add top-level CSS module

[cdepillabout]

This pull-request adds a top-level CSS module that exports all the the CSS.* sub-modules, except for CSS.Render. It also removes an uneeded import from the testing file.

One small problem is that maxWidth is exported from both CSS.Geometry and CSS.Media. I hid the maxWidth from CSS.Media. I made this decision pretty much arbitrarily, so if you think something else should be done, let me know.

Also, please let me know if there are modules other than CSS.Render that shouldn't be exported.

[puffnfresh]

Thank you! I've wanted this, PureScript just didn't have re-exports at the time.

👍

[garyb]

Thanks! 👍

Maybe we should omit the entire re-export of CSS.Media rather than hiding the conflicting name, as it might be confusing as to why the maxWidth in scope doesn't work for a Feature value, but other Media-related things do? I don't mind too much either way though.

[cdepillabout]

@garyb: Sounds good. I removed the export of CSS.Media.

[garyb]

Thanks!