SourceTree should be source-tree, not sourcetree

According to https://github.com/phinze/homebrew-cask/issues/365
Add naming convention (discussion).
Add iterm2 beta.
Merge pull request #1426 from kud/feat.iterm2-beta

Add iterm2 beta.
sudo the rmdir on pkg uninstall

fixes an issue we've hit where chmod 777 is insufficient to allow
Pathname#rmdir to work properly.

refs #1374
Merge pull request #1427 from phinze/1374-fix-uninstall-permissions

sudo the rmdir on pkg uninstall
cut v0.19.4
Merge pull request #1425 from kud/feat.contributing

Add naming convention (discussion).
airmail-beta 1.2.1
Merge pull request #1429 from alexg0/airmail-beta

Airmail-beta 1.2.1
Update Air Server
Merge pull request #1431 from linc01n/air-server

Update Air Server
Update OmniDiskSweeper to use latest scheme
Pastor 1.8.2
Merge pull request #1432 from leoj3n/pastor-1.8.2

Pastor 1.8.2
Update OmniDiskSweeper URL

URL was changed from omnidisksweeper to OmniDiskSweeper
TimeMachineScheduler beta
Instacast 1.0.4
Merge pull request #1433 from alexg0/time-machine-scheduler-beta

TimeMachineScheduler beta
iPhoney 1.2