Install Disk Image should be nicer and include link to Application Folder

[knutigro]

• http://stackoverflow.com/questions/1713227/how-to-create-drag-and-drop-dmg-file-mac-installer
• http://stackoverflow.com/questions/96882/how-do-i-create-a-nice-looking-dmg-for-mac-os-x-using-command-line-tools
• http://stackoverflow.com/questions/871551/add-background-image-color-to-dmg-using-hdiutil-or-other-tool