Auto merge of servo#91 - servo:macro, r=SimonSapin

Make match_ignore_ascii_case! future-proof.

Change the usage syntax to require a comma on the last non-fallback arm, which is a [breaking-change].

The old definition has started to emit a warning in recent nightlies and is likely to be an error in future versions: rust-lang/rfcs#1384

The new definition is recursive to resolve ambiguities. Unfortunately this makes error reporting terrible: rust-lang/rust#31022

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Auto merge of servo#89 - servo:serialization-separators, r=mbrubeck

Add "token serialization types".

Servo will use this for custom property values which are conceptually sequences of tokens, but are represented in memory as strings. When concatenating such strings, an empty comment `/**/` sometimes needs to be inserted so that two tokens are not reparsed as one.

r? @pcwalton

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Fix handling of Delimiter::Bang

Auto merge of servo#88 - servo:bang, r=SimonSapin

Add Delimiter::Bang for CSS Custom Properties.



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Auto merge of servo#82 - metajack:release-0.3.4, r=SimonSapin

Bump version number for release.

r? @SimonSapin

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Remove some default associated types, so that default methods don’t h…

…ave to be overridden.

Since rust-lang/rust#26728 , Servo would get build errors like:

    error: the following trait items need to be reimplemented as `AtRule` was overridden: `rule_without_block` [E0399]
        type AtRule = CSSRule;
        ^~~~~~~~~~~~~~~~~~~~~~