update version number

Cargo.toml

 [package]
 name = "coap"
-version = "0.4.0"
+version = "0.5.0"
 description = "A CoAP library"
 readme = "README.md"
 documentation = "http://covertness.github.io/coap-rs/coap/index.html"

README.md

@@ -17,7 +17,7 @@ First add this to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-coap = "0.4"
+coap = "0.5"
 ```
 
 Then, add this to your crate root:

src/lib.rs

@@ -11,7 +11,7 @@
 //!
 //! ```toml
 //! [dependencies]
-//! coap = "0.3"
+//! coap = "0.5"
 //! ```
 //!
 //! Then, add this to your crate root:
@@ -31,7 +31,9 @@
 
 //! fn request_handler(request: CoAPRequest) -> Option<CoAPResponse> {
 //! 	println!("Receive request: {:?}", request);
-//!     None
+//!     
+//!     // Return the auto-generated response
+//!     request.response
 //! }
 
 //! fn main() {