Add the OmniFocus beta/test builds

This commit adds the OmniFocus beta/test stream.

Casks/omnifocus-beta.rb

@@ -0,0 +1,18 @@
+cask :v1 => 'omnifocus-beta' do
+  version '2.2.x-r233653'
+  sha256 '6dbec967be6ad55dc6def5c3284979257e2c10e7a6d9fa3b09c1abd587ac7172'
+
+  url "http://omnistaging.omnigroup.com/omnifocus-2/releases/OmniFocus-#{version}-Test.dmg"
+  name 'OmniFocus'
+  homepage 'http://omnistaging.omnigroup.com/omnifocus-2/'
+  license :commercial
+
+  app 'OmniFocus.app'
+
+  zap :delete => [
+                  '~/Library/containers/com.omnigroup.omnifocus2',
+                  '~/Library/Preferences/com.omnigroup.OmniFocus2.LSSharedFileList.plist',
+                  '~/Library/Preferences/com.omnigroup.OmniSoftwareUpdate.plist',
+                  '~/Library/Caches/Metadata/com.omnigroup.OmniFocus2'
+                 ]
+end