overhault to fix warnings etc

src/db.rs

@@ -46,8 +46,8 @@ pub fn has_table(
     use diesel::sql_types::Text;
     #[derive(QueryableByName)]
     struct TableName {
-        #[sql_type = "Text"]
-        #[column_name = "name"]
+        #[diesel(sql_type = Text)]
+        #[diesel(column_name = name)]
         name: String,
     }