The old type configuration
(`platypush.plugins.calendar.name.CalendarNamePlugin`) is a bit clunky.
Instead, since the type will always be a plugin, we should encourage
the use of `calendar.name` directly to identify the type.
The error should not be swallowed and it should be instead propagated up
to calendar.get_upcoming_events, if it's called from that context. And
calendar.get_upcoming_events should be in charge of handling the
exceptions and make sure that failing to retrieve the events for one
calendar doesn't make the whole method fail.
- Using `@action` annotation to indicate methods that are allowed to be
executed as actions
- The output and errors of an action are automatically wrapped into a
`Response` object without any response build required on the plugin side