Fix some issues pointed out by Clippy in examples and tests (#172)

In case of writing data, the code looks like it expects all data to be
written. And in case of reading data it expects some data to be read.
Let's make this explicit.

examples/clear_input_buffer.rs

@@ -125,7 +125,7 @@ fn input_service() -> mpsc::Receiver<()> {
                     drop(tx); // EOF, drop the channel and stop the thread
                     break;
                 }
-                Ok(_) => tx.send(()).unwrap(), // Signal main to clear the buffer
+                Ok(_bytes_read) => tx.send(()).unwrap(), // Signal main to clear the buffer
                 Err(e) => panic_any(e),
             }
         }

examples/clear_output_buffer.rs

@@ -85,7 +85,7 @@ fn run(port_name: &str, baud_rate: &str, block_size: usize) -> Result<(), Box<dy
     // This loop writes the block repeatedly, as fast as possible, to try to saturate the
     // output buffer. If you don't see much data queued to send, try changing the block size.
     loop {
-        match port.write(&block) {
+        match port.write_all(&block) {
             Ok(_) => (),
             Err(ref e) if e.kind() == io::ErrorKind::TimedOut => (),
             Err(e) => panic!("Error while writing data to the port: {}", e),
@@ -125,7 +125,7 @@ fn input_service() -> mpsc::Receiver<()> {
                     drop(tx); // EOF, drop the channel and stop the thread
                     break;
                 }
-                Ok(_) => tx.send(()).unwrap(), // Signal main to clear the buffer
+                Ok(_bytes_read) => tx.send(()).unwrap(), // Signal main to clear the buffer
                 Err(e) => panic_any(e),
             }
         }

tests/test_tty.rs

@@ -98,7 +98,7 @@ fn test_osx_pty_pair() {
     let (output_sink, output_stream) = std::sync::mpsc::sync_channel(1);
     let name = slave.name().unwrap();
 
-    master.write("12".as_bytes()).expect("");
+    master.write_all("12".as_bytes()).expect("");
 
     let reader_thread = std::thread::spawn(move || {
         let mut port = TTYPort::open(&serialport::new(&name, 0)).expect("unable to open");