[EnderStorage] StorageManager crashes when sending packet to player under certain conditions.

[covers1624]

@Time6628

CodeChicken/EnderStorage tries to send a packet to the player before the player is connected, so the player is null which causes the server to crash.

Crash report: https://gist.github.com/Time6628/5839e1cf184ecc79871228025a5ba184

Pull request from 1.7.10 with the same/similar NPE: Chicken-Bones/CodeChickenLib#54

[covers1624]

Seems EnderStorage was trying to send packets to the player on logout, that could entirely break on sponge or other server platforms. Surprised that it didn't break more often..