Merge pull request #248 from skyboy/master

Add comparator output override
Merge pull request #249 from skyboy/master

Integer division >.<
Merge pull request #254 from skyboy/master

Clean rubber tree gen code
Merge pull request #256 from skyboy/master

Renamed jailer safarinet names released mobs.
isEmpty is true on stacks with NBT but no mob ID
Cleanup: null instanceof Foo (returns false/is safe)

"te != null && te instanceof Foo" -> "te instanceof Foo"

instanceof will just return false on null anyway
Merge remote-tracking branch 'upstream/master'