Implement editing/opening a single note in the editor

[DrStrangeloovee]

The functionality to view/open/edit a note has to be implemented. The notelist component already fetches the needed information (id) to retrieve a specific note.
To implement:

• [x] Endpoint to fetch note contents
• [x] Feed retrieved content into the editor component
• [x] Implement editor route note?id=noteId
• [x] Transition to editor route
• [x] Implement new note route note/new