Extremely small OCD fix

Just had to do it.
Fix iTerm split behavior
If using splits inside iTerm, Shuttle was openining hosts into the last
open split and disregarding the newly-created tab.
See #5.
Merge pull request #35 from Thoro/Default-Config

Create default config file during awakeFromNib instead of when loading menu
Merge pull request #40 from imryan/patch-1

minor cleanup
Merge pull request #37 from Thoro/OpenUrls

Added capability to open urls of all kinds
Add contributors
Merge pull request #2 from fitztrev/master

Merge fitztrev/shuttle:master