Implement the http variant of the bank server.

During that process, many shortcomings with the socket server and the
bank lib were fixed.

I am aware a massive commit like this is not ideal.

socket-server/src/commands/create_account.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct CreateAccount;
 
 impl Command for CreateAccount {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         debug!("owner nr bytes {:?}", data);
 
         let owner = String::from_utf8_lossy(data);
@@ -25,4 +30,4 @@ impl Command for CreateAccount {
         let written = stream.write(&protocol::account_nr(&nr))?;
         Ok(written)
     }
-}
+}