Include nobt title in URL for better SEO

[thomaseizinger]

Currently, the URL for a nobt is only the ID returned from the server.

This makes it hard for humans to differentiate between several different nobts they might have saved in their browser history.

Also, autocomplete in the browser searchbar is relatively hard to impossible and only works with the nobt's title if the browser searches the document title as well.

This issue proposes to extend the URL to something like:

http://nobt.io/nova-rock-2019-d83kgh7Gdk20z

Open questions:

1. Should this functionality be built in the frontend or the backend?

The backend could offer functionality for fetching a nobt through this composite ID + include the paths for actions like 'create-bill' or 'add-payment' so that the frontend doesn't have to do the parsing.

2. How to handle backwards compatiblity to old URLs?

Those MUST still work bc the URL is the only thing the users have in order to access the nobt.