Auto merge of #188 - mbrubeck:docs, r=jdm

Link to docs.rs for documentation

because doc.servo.org might not always have the same version as crates.io

Author: bors-servo

Cargo.toml

@@ -9,7 +9,7 @@ description = "'Small vector' optimization: store up to a small number of items
 keywords = ["small", "vec", "vector", "stack", "no_std"]
 categories = ["data-structures"]
 readme = "README.md"
-documentation = "https://doc.servo.org/smallvec/"
+documentation = "https://docs.rs/smallvec/"
 
 [features]
 write = []