fixed warning (#912)

components/link_checker/src/lib.rs

@@ -6,7 +6,6 @@ use config::LinkChecker;
 use errors::Result;
 
 use std::collections::HashMap;
-use std::error::Error;
 use std::sync::{Arc, RwLock};
 
 #[derive(Clone, Debug, PartialEq)]
@@ -96,7 +95,7 @@ pub fn check_url(url: &str, config: &LinkChecker) -> LinkResult {
                 LinkResult { code: None, error: Some(error_string) }
             }
         }
-        Err(e) => LinkResult { code: None, error: Some(e.description().to_string()) },
+        Err(e) => LinkResult { code: None, error: Some(e.to_string()) },
     };
 
     LINKS.write().unwrap().insert(url.to_string(), res.clone());