Bump werkzeug from 0.11.10 to 0.15.3

Bumps [werkzeug](https://github.com/pallets/werkzeug) from 0.11.10 to 0.15.3.
- [Release notes](https://github.com/pallets/werkzeug/releases)
- [Changelog](https://github.com/pallets/werkzeug/blob/master/CHANGES.rst)
- [Commits](pallets/werkzeug@0.11.10...0.15.3)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -22,5 +22,5 @@ python-editor==1.0.1
 six==1.10.0
 SQLAlchemy==1.0.14
 visitor==0.1.3
-Werkzeug==0.11.10
+Werkzeug==0.15.3
 WTForms==2.1