VPN should connect automatically

[ralxxx]

Setting-up a VPN connection is really easy, that's good. But after closing the lid or rebooting the device the VPN connection never goes back online automatically. At least on my device (Thinkpad t460s) this does not happen.

As it should be:

• VPN should work similar to Wifi: Once the toggle was switched on by the user, on every restart of the device eOS should reconnect automatically to one of the VPN registered within the system.
• Furthermore there should be an easy to find killswitch setting to make sure that the device really only connects with VPN running.

[auryn-macmillan]

You can set any connection to automatically connect to a specified VPN in the advanced settings for the connection.