User feedback & Toast to ApplicationContext

- The Renew last connection button now disables while a connection
attempt is ongoing, providing the user click feedback at the same time.
- A Toast now appears when the user starts combining points (click
feedback).
- Blank workspace fields now allowed in SrvEditor.
- Toast are now LENGTH_LONG by default and are published to the
ApplicationContext rather than any Activity.
- Panning to location on showAcceptLocationDialog() made dependent on
boolean parameter.