Arcing egg transition between runners and refactor positioning.

Closes #31, Closes #71
Closes #32 - Handle runner death in a number of cases with the egg
New Egg Texture.
Rotate egg while it's moving between runners.
Hide egg when team dies.
Prevent double invocation of throwing.
Fix egg tutorial signs.
Closes #58 - Commander can allow runner with egg to jump.
Fix player holding egg running during countdown.
Improve swipe detection and support directional throwing.
Fix playing with egg disabled.
Merge branch 'egg-improvements'