chg: [ui] improved forms in navbar.

Display some information about the instance in the about/more page.

Refactoring the backend.

Improved method to detect current version  of the Newspipe instance.

Removed Flask-SSLify and Heroku default support.

The project is now using Poetry.

Updated URL to home page of the project.

Merge branch 'master' of gitlab.com:newspipe/newspipe

Updated some links

Updated translations.

merge and fixed conflict

Added registration status.

Displays if the the instance is running on Heroku.

Added a page which displays some information about the instance.