Implement Path Finding

[Paxi]

This should work for the EntityPlayerSP, unlike currently existing versions made by Mojang for Zombies and stuff.

This should account for:

Bunnyhopping (Can I sprint-jump without getting rekt?)
Sprinting (Bunnyhopping not possible? Just sprint)
Normal walking (Exhausted? Just walk)

It should obviously avoid any harmful blocks and swimming should be optional.