Indicate upcoming downtimes as gray pylon in GUI.

Active downtimes for servers/services are indicated in the GUI with the orange pylon icon and are thus immediately visible to the user.

Planned server/service downtimes, on the other hand, are only visible in the corresponding downtime view. The user does not see directly if a downtime is planned for a server/service.

It would be a greate help for the User if also planned downtimes could be indicated in the GUI. For example with a gray pylon. This way it would be immediately visible in the GUI that a downtime has been planned for this server/service.