Added 152x152 icon suitable for Apple devices.
See https://developer.apple.com/library/ios/documentation/AppleApplications/Reference/SafariWebContent/ConfiguringWebApplications/ConfiguringWebApplications.html

git-svn-id: http://blockly.googlecode.com/svn/trunk@1592 c400ca83-b69d-9dd7-9705-49c6b8615e23