Add dynamic, map and serde modules.

src/lib.rs

@@ -1,3 +1,4 @@
+#[cfg(feature="wav")] extern crate hound;
 extern crate instrument;
 extern crate pitch_calc as pitch;
 extern crate sample;
@@ -7,8 +8,12 @@ pub use map::{Audio, Map, Sample};
 pub use mode::Mode;
 pub use sampler::{Frames, Sampler};
 
-mod map;
+pub mod dynamic;
+pub mod map;
 mod mode;
 mod sampler;
 
+#[cfg(feature="serde_serialization")]
+mod serde;
+
 pub type Velocity = f32;