Auto merge of servo#98 - nox:bump-serde, r=KiChjang

Bump serde to 0.7

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "cssparser"
-version = "0.5.3"
+version = "0.5.4"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"
@@ -17,11 +17,11 @@ rustc-serialize = "0.3"
 tempdir = "0.3"
 
 [dependencies.serde]
-version = "0.6.6"
+version = ">=0.6.6, <0.8"
 optional = true
 
 [dependencies.serde_macros]
-version = "0.6.5"
+version = ">=0.6.5, <0.8"
 optional = true
 
 [dependencies.heapsize]