Added more Flask extensions to install_requires

Added the followqing Flask Extensions: 'Flask-MongoAlchemy>=0.6.1', 'flask-script', 'flask-bootstrap', 'flask-moment', 'flask-wtf', 'flask-sqlalchemy', 'flask-migrate', 'flask-mail', 'flask-login', 'forgerypy', 'flask-pagedown', 'markdown', 'bleach', 'flask-httpauth'