RC1 1.0.0

Release Candidate 1 for version 1.0.0.

What's Changed

• Fix deadlock when calling command within command_error handler by @andrewsayre in #59
• Add remaining Group commands by @andrewsayre in #61
• Add Get Player Info by @andrewsayre in #63
• Add check update command by @andrewsayre in #64
• Add Player Queue Commands by @andrewsayre in #65
• Add remaining browse commands by @andrewsayre in #68
• Refactor consts by @andrewsayre in #71
• Add enums for player fields by @andrewsayre in #73
• Refactor internals by @andrewsayre in #76
• Add incremental backoff by @andrewsayre in #78
• Add add_search_to_queue by @andrewsayre in #80
• Combine mixins with command creation by @andrewsayre in #82

Full Changelog: 0.9.0...1.0.0-rc1