Document libssl-dev dependency in README

README.md

@@ -238,6 +238,11 @@ If your rustc version is lower than 1.26.1, please update it:
 $ rustup update
 ```
 
+On Linux systems you may need to install libssl-dev.  On Ubuntu:
+```bash
+$ sudo apt-get install libssl-dev
+```
+
 Download the source code:
 
 ```bash

src/thin_client.rs

@@ -162,7 +162,7 @@ impl ThinClient {
         let data = serialize(&req).expect("serialize GetLastId in pub fn get_last_id");
         let mut done = false;
         while !done {
-            eprintln!("get_last_id send_to {}", &self.requests_addr);
+            debug!("get_last_id send_to {}", &self.requests_addr);
             self.requests_sender
                 .send_to(&data, &self.requests_addr)
                 .expect("buffer error in pub fn get_last_id");