eldbus - make method calls less crasy since libdbus likes to abort

eldbus - make method calls less crasy since libdbus likes to abort

changes zmike made to e's systray make e abort due to libdbus seeing
the bus name as invalid. it actually is. it's
/org/ayatana/NotificationItem/steam for example - instead of
or.whatever.blah - thuis e aborts continually if you run steam at all.
eldbus should be more crash-proof thus this adds checks so dbus fun
doesnt cause an app to crash if it happens to call incorrect dbus names.

@fix