Create default config

Moved the default config creation to awakeFromNib, because if neither
ssh_config nor config exist, it never get's created
Added capability to open urls of all kinds

Before opening a command in a terminal, the command is checked and if
it's a url it's opened.

Useful for custom url schemes.
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 branch 'master' of https://github.com/fitztrev/shuttle

Conflicts:
	Shuttle/AppDelegate.m