Update README.md

Fixed Git guide URL
Update README.md

Removed "unfinished" note from the How To Git URL.

Don't forget to read the important Feb 23rd repo changes: https://github.com/Double-Fine-Game-Club/bad-golf-community-edition/wiki/How-To-Git#wiki-23rd-of-february-history-changes
hide the arrows until you've actually joined and hover tint sprites, also remove automatic anchoring due to crazy bug, swapped for a checkbox that applies the automatic on checkmark
Merge branch 'master' into localmulti_02