Describe the bug
The balloon and extra jump height from armor doesn't stack.

To Reproduce
Steps to reproduce the behavior:
Wear a balloon and something with extra jump height armor (like springy quality.)

Expected behavior
I should be jumping at least the height of the balloon (plus the little extra), but instead it ignores the balloon and only jumps via the armor extra. The balloon allows jumping up 3 blocks, while with both on I am only able to jump up 2 blocks.

Screenshots

Info (please complete the following information):

• Modpack Version: 2.77.5
• Server or Singleplayer: Singleplayer
• Version the world was created on: 2.77.5

Additional context

Duplicate of #112