Fix TSV output in web UI

Author: billzt

primerserver2/core/version.py

@@ -1,2 +1,2 @@
 def get():
-    return '2.0.0b16'
+    return '2.0.0b17'

primerserver2/web/download.py

@@ -9,5 +9,5 @@
 def download_tsv():
     json_data = json.loads(request.form['json'])
     dbs = request.form['dbs'].split(',')
-    print_lines = output.tsv(json_data['primers'], dbs)
+    print_lines = output.tsv(json_data['primers'], dbs, json_data['meta']['mode'])
     return print_lines