Split up test suite so it compiles in parallel

test_suite/tests/test_ser.rs

@@ -1,9 +1,14 @@
+#[macro_use]
+extern crate serde_derive;
+
 use std::collections::{BTreeMap, HashMap, HashSet};
 use std::net;
 use std::path::{Path, PathBuf};
 use std::str;
 use std::time::Duration;
 
+extern crate serde;
+
 extern crate serde_test;
 use self::serde_test::{
     Error,
@@ -18,6 +23,9 @@ use self::fnv::FnvHasher;
 #[cfg(feature = "unstable")]
 use serde::ser::iterator;
 
+#[macro_use]
+mod macros;
+
 //////////////////////////////////////////////////////////////////////////
 
 #[derive(Serialize)]