Factor the Token De/Serializer into serde_test

serde_test/src/lib.rs

@@ -0,0 +1,22 @@
+extern crate serde;
+
+mod assert;
+pub use assert::{
+    assert_tokens,
+    assert_ser_tokens,
+    assert_ser_tokens_error,
+    assert_de_tokens,
+    assert_de_tokens_error,
+};
+
+mod ser;
+pub use ser::Serializer;
+
+mod de;
+pub use de::Deserializer;
+
+mod token;
+pub use token::Token;
+
+mod error;
+pub use error::Error;