Upgrade cssparser to a version with the new ToCss trait.
Implement ToCss for types in style::properties::common_values::specified
Implement ToCss for Cursor and de-duplicate variants and string values.
Remove some tabs

@jdm, can you configure your editor to not insert them in the first
place?
Declare dependencies on text_writer.

Transitive dependencies being available is considered a bug:
https://github.com/rust-lang/cargo/issues/1037
Add a match_ignore_ascii_case! macro that does not allocate.

It should replace `match foo.to_ascii_lower().as_slice() { ...}`

@Manishearth I changed map.get to map.find in the lint to work around an ICE:

    task 'rustc' panicked at 'couldn't find node id 0 in the AST map'

Does this look OK?
Fix typo in a cursor keyword. Thanks @nuss-justin!
Move the define_css_keyword_enum macro to the style crate.
auto merge of #4455 : servo/servo/to_css, r=jdm

See https://github.com/servo/rust-cssparser/pull/67 and https://github.com/servo/servo/issues/4440.

r? @jdm