Data models introduction

• Introduced data models
  • DBLClient.get_bot_votes now returns a list of BriefUserData objects
  • DBLClient.get_bot_info now returns a BotData object
  • DBLClient.get_guild_count now returns BotStatsData
  • DBLClient.get_user_info now returns UserData
• WebhookManager.run now returns an asyncio.Task, meaning it can now be optionally awaited