Add initial support for modern JPEG compression

Some things still need to be done:
- Check RGB images
- Check small images
- Check huffman-only jpeg tables
- Check empty jpeg tables
- Add tests

src/lib.rs

@@ -8,6 +8,7 @@
 
 extern crate miniz_oxide;
 extern crate weezl;
+extern crate jpeg;
 
 mod bytecast;
 pub mod decoder;