Most of the way to no_std support

lib/native/Cargo.toml

@@ -15,3 +15,6 @@ cretonne = { path = "../cretonne", version = "0.1.0" }
 
 [target.'cfg(any(target_arch = "x86", target_arch = "x86_64"))'.dependencies]
 raw-cpuid = "3.0.0"
+
+[features]
+no_std = ["cretonne/no_std"]

lib/native/src/lib.rs

@@ -1,6 +1,6 @@
 //! Performs autodetection of the host for the purposes of running
 //! Cretonne to generate code to run on the same machine.
-
+#![cfg_attr(feature = "no_std", no_std)]
 #![deny(missing_docs)]
 
 extern crate cretonne;