Sending end of the wallet

Most of the logic to build a transaction that sends coin to
another party. Still requires more debugging and clean up.
Main changes and additions are:

* Update to serde 1.0
* API endpoint to retrieve an Output
* Output is now Serialize and Deserialize
* Wallet configuration
* Command line for the send operation
* Wallet data checker to update created outputs into confirmed
* Wallet-specific configuration

api/src/client.rs

@@ -26,8 +26,9 @@ use rest::Error;
 /// returns a JSON object. Handles request building, JSON deserialization and
 /// response code checking.
 pub fn get<'a, T>(url: &'a str) -> Result<T, Error>
-	where T: Deserialize
+	where for<'de> T: Deserialize<'de>
 {
+  println!("get {}", url);
 	let client = hyper::Client::new();
 	let res = check_error(client.get(url).send())?;
 	serde_json::from_reader(res)
@@ -40,7 +41,7 @@ pub fn get<'a, T>(url: &'a str) -> Result<T, Error>
 /// checking.
 pub fn post<'a, IN, OUT>(url: &'a str, input: &IN) -> Result<OUT, Error>
 	where IN: Serialize,
-	      OUT: Deserialize
+	      for<'de> OUT: Deserialize<'de>
 {
 	let in_json = serde_json::to_string(input)
 		.map_err(|e| Error::Internal(format!("Could not serialize data to JSON: {}", e)))?;