Cleanups, visibility fixes, add authors

src/lib.rs

@@ -11,9 +11,7 @@ extern crate lzw;
 extern crate num_traits;
 #[macro_use] extern crate enum_primitive;
 
-pub use self::decoder::TIFFDecoder;
-
-mod decoder;
+pub mod decoder;
 mod error;
 
 pub use self::error::{TiffError, TiffResult};