Option to blacklist plugins from showing on the menu

We have a way of whitelisting the plugins that we want to show on the menu with <window><plugins><show>, as explained on this tutorial. It would be nice to have a way of blacklisting a few plugins too.

Desired behavior

All plugins from the paths are shown on the menu except for the ones explicitly blacklisted.

Alternatives considered

:thinking:

Implementation suggestion

Similar to the show implementation here:

https://github.com/ignitionrobotics/ign-gui/blob/1cad501ad0c7da9f7811efa75ed3af80e5ee6a07/src/MainWindow.cc#L465-L472

We could have a hide.

We should make sure it plays well with show and from_paths.

Additional context

It would be nice to blacklist plugins we don't want users to try out yet, or plugins that don't work well when inserted from the menu.