added iterm2-legacy 2.1.4 (#2297)

* added iterm2-legacy 2.1.4

this is a port of the formula from caskroom/homebrew-cask; i'm adding
this because there are backwards incompatibilities between iterm2 2.x
and iterm2 3.x, and people may need to stay on 2.x

Casks/iterm2-legacy.rb

@@ -0,0 +1,19 @@
+cask 'iterm2-legacy' do
+  # note: "2" is not a version number, but indicates a different vendor
+  version '2.1.4'
+  sha256 '1062b83e7808dc1e13362f4a83ef770e1c24ea4ae090d1346b49f6196e9064cd'
+
+  url "https://iterm2.com/downloads/stable/iTerm2-#{version.dots_to_underscores}.zip"
+  name 'iTerm2'
+  homepage 'https://www.iterm2.com/'
+  license :gpl
+
+  auto_updates true
+  conflicts_with cask: 'iterm2'
+  depends_on macos: '>= :lion'
+  depends_on arch: :intel
+
+  app 'iTerm.app'
+
+  zap delete: '~/Library/Preferences/com.googlecode.iterm2.plist'
+end