This plugin will display a notification each time a package with type
"kdeconnect.telephony" is received. The type of notification will change
depending on the contents of the field "event" (string).
Valid contents for "event" are: "ringing", "talking", "missedCall" and "sms".
Note that "talking" is just ignored in this implementation, while the others
will display a system notification.
If the incoming package contains a "phoneNumber" string field, the notification
will also display it. Note that "phoneNumber" can be a contact name instead
of an actual phone number.
If the incoming package contains "isCancel" set to true, the package is ignored.
