Don't package big-data-url.css and color3_hsl.json

[jdm]

They are files that are >100k and trigger the large file error when vendoring in mozilla-central. If we could avoid packaging them, that would be nice.

[SimonSapin]

http://doc.crates.io/manifest.html#the-exclude-and-include-fields-optional

[SimonSapin]

If we’re removing test files all of src/css-parsing-tests should also be removed, even files under 100k.