Custom Scoreboard

Additions:

• Option to hide consecutive separators.
• Option to hide separators at the top/bottom of the scoreboard.

Changes:

• Changed Update Notifier to only alert on Server join, and not on world switches.

Fixes:

• Fixed Background Rendering on MacOs.
• Fixed the Party Element sometimes containing members twice.
• Fixed Update Notifier alerting for updates on the wrong minecraft version.