For now, it supports only one system tray icon per application.
Each instance of ELM_OBJ_SYSTRAY_CLASS is a handler for
the same system tray item. But the API is ready to support
multiple system tray items per application.
Also, since this is a new feature, it only provides an EObject API. So,
if the old style API is still required, please do it.
Patch by: Murilo Belluzzo <murilo.belluzzo@profusion.mobi>
SVN revision: 81747