Update exercise2.jv

Author: anosh-ar

exercises/exercise2.jv

@@ -21,7 +21,7 @@ pipeline treesPipeline {
      treesTextFileInterpreter
         -> treesCSVInterpreter 
         //-> NameHeaderWriter
-        -> DBAColumnDeleter
+        //-> DBAColumnDeleter
         -> treesTableInterpreter
         -> treesLoader;
 
@@ -112,4 +112,4 @@ pipeline treesPipeline {
     // 16. Congratulations!
     // You can now use the sink for your data analysis, app, 
     // or whatever you want to do with the cleaned data.  
-}
+}