Adds arrow arc

fixes #1854

This adds a slight arc to the arrow so that pierce can hit acorns with arrows.

I didn't add much of an arc but everything can be changed (quite easily), Do we want more of an arc? Less of an arc? Faster arrow? Slower?

I set it like this so you could still hit acorns from a reasonable distance, but maybe we want more of an arc to change the entire mechanic of arrows? Make them less overpowered?