Discord polls

[UncleVasya]

Create discord polls for inhouse. Polls are automatically connected to inhouse settings in db.

• [x] poll channels id in LadderSettings;
• [x] Poll model:
  • poll name;
  • discord message id;
• [x] if not present in channel, create poll messages;
• [x] add DefaultDraftMode to LadderSettings: playerdraft of autobalance;
• [x] update poll message based on current settings;
• [x] on reaction add event:
  • [x] check that reaction is in poll reaction variants;
  • [x] check that user is known and can vote (has 5+ games for example);
  • [x] check if user already voted for another variant;
  • [x] remove incorrect reactions;
  • [x] calculate votes, update settings and poll message;
• [x] on reaction remove event:
  • [x] calculate votes, update settings and poll message;

[UncleVasya]

Done.