Add legacy version QuickTime Player 7

This commit includes legacy QuickTime Player version 7.6.6.  The DMG
contains the string "SnowLeopard", but this binary is not specific to
Snow Leopard.  It runs on any OS X from Snow Leopard through Mavericks.

Casks/quicktime-player-7.rb

@@ -0,0 +1,9 @@
+class QuicktimePlayer7 < Cask
+  url 'http://support.apple.com/downloads/DL923/en_US/QuickTimePlayer7.6.6_SnowLeopard.dmg'
+  homepage 'http://support.apple.com/kb/dl923'
+  version '7.6.6'
+  sha1 '5a4d572aca134c4ea5c4646d4def41c8ef04e7c9'
+  install 'QuickTimePlayer7.6.6_SnowLeopard.pkg'
+  uninstall :pkgutil => 'com.apple.pkg.QuickTimePlayer7.6.6_SnowLeopard',
+            :files   => '/Applications/Utilities/QuickTime Player 7.app'
+end