Add back crate_name for rustdoc

Closes #10

phf/src/lib.rs

@@ -5,6 +5,7 @@
 #![doc(html_root_url="http://www.rust-ci.org/sfackler")]
 #![warn(missing_doc)]
 #![feature(macro_rules)]
+#![crate_name="phf"]
 
 use std::fmt;
 use std::iter;

phf_mac/src/lib.rs

@@ -3,6 +3,7 @@
 //! See the documentation for the `phf` crate for more details.
 #![doc(html_root_url="http://sfackler.github.io/rust-phf/doc")]
 #![feature(plugin_registrar, quote, default_type_params, macro_rules)]
+#![crate_name="phf_mac"]
 
 extern crate rand;
 extern crate syntax;