[REQUEST] Add Last.fm Scrobbler for osu!player

[AyanoKiru]

Describe the solution you'd like Allows user to scrobble play counts to last.fm and love or ban tracks with the "loved" field.

Note from Founntain:

We need to look into that how we can implement that. Probably using the Last.fm API for that. However we need to check how we implement that properly

• [x] Implement Last.FM Service
• [x] Give user the ability to enter their API-Key and Secret and get their SessionKey
• [x] Storing the SessionKey
• [x] Send Scrobble Data to the Last.fm API
• [x] Refactor and checking for API Limits

[Founntain]

Added todo to the original issue comment, to keep track of stuff