0.9.0 Start Party and send/receive requests

[mrf7]

Step 4: Build the rest of the app
End Goal is an actually usable (but not pretty) MVP app.

• Start a party and get a unique party code to share with other users
• Join a party by entering a party code
• Send requests to the party host by sharing from spotify
  • Implement song search functionality?
• Review requests in a list view with check and X buttons. Both remove from Firebase
• Ending party deletes from firestore, giving guests indication that the party ended.