Added app.py and caretta/pfam.py

bin/carettapp-demo

@@ -441,7 +441,7 @@ def write_output(clicked, clicked_all, chosen_feature, feature_dict, aln):
 def downlad_file(path):
     root_dir = os.getcwd()
     return flask.send_from_directory(
-        os.path.join(root_dir, 'caretta/static'), path)
+        os.path.join(root_dir, '/caretta/static'), path)
 
 
 @app.callback([dash.dependencies.Output("feature-line", "figure"),