Fixed bug with Ice Fishing in the Nether

Fixes  #1218
Realized that it wasn't only happening in the Nether
Make UpdateChecker run asynchronously and not block startup

Closes #1049
Update the changelog: Fixed update check
Disable mob healthbars for boss mobs!

Fixes #1210
Minor cleanup
Fixed bug with Ice Fishing which allowed players to break protected blocks

Fixes #2074
Localize the ScoreboardManager

Closes #1232
Pretty sure this should be Fake
Pull changes from dev-dbman (commit f63c5e3)