Cleanup quotes :)

Prefer double quotes to singe.
Add Flask-FlatPages support

Flask-FlatPages provides a collections of pages to your Flask
application. Pages are built from “flat” text files as opposed to a
relational database.
Add Frozen-Flask support

Frozen-Flask freezes a Flask application into a set of static files.
The result can be hosted without any server-side software other than a
traditional web server.