icon — Defines the icon to appear in the titlebar of a ReST application
when referencing this ReST package.
If icon is given in
explorerattributes, installerattributes,
monitorattributes and icon will appear in the titlebar
of the related ReST application when referencing this package.
The following elements are valid parents of icon:
explorerattributes, installerattributes, monitorattributes.