Added the signature for passing filters into the render function.

Added the signature for passing filters into the render function but I am not yet using the filters.

src/lib.rs

@@ -1,7 +1,4 @@
 extern crate nom;
 
-mod parser;
-mod renderer;
-
-pub use renderer::compile_template;
-pub use renderer::DustRenderer;
+pub mod parser;
+pub mod renderer;