Add Processing v2.2.1 (#2427)

Casks/processing2.rb

@@ -0,0 +1,17 @@
+cask 'processing2' do
+  version '2.2.1'
+  sha256 '8c237b3eb50626e8ffc648bfdeddaa18ceffbd6a48f8fec77a8eab5b774971fc'
+
+  url "http://download.processing.org/processing-#{version}-macosx.zip"
+  appcast 'https://github.com/processing/processing/releases.atom',
+          checkpoint: 'b731bdafbc7e9c7c9026d6a8c124c0dfc48d18f502fd7ae89cc445dc0bd02bee'
+  name 'Processing'
+  homepage 'https://processing.org/'
+  license :gpl
+
+  conflicts_with cask: 'processing'
+
+  app 'Processing.app'
+
+  zap delete: '~/Library/Processing/preferences.txt'
+end