Add more error reporting for DB loading

src/main.rs

@@ -141,11 +141,13 @@ fn read_from_db(config: HashMap<String, String>, mut predictor: SetPredictor) ->
                     predictor
                 },
                 Err(e) => {
+                    println!("Error while reading from DB: {}", e);
                     predictor
                 }
             }
         },
         Err(e) => {
+            println!("Error while connecting to DB: {}", e);
             predictor
         }