Add client option to re-establish connection

[Doug Doole]

A wish list item for me...

I frequently use xpra over a VPN connection. Inevitably, the VPN connection goes down at some point. When that happens, I have to disconnect xpra and then start it again after re-establishing the VPN link.

I'd love it if there was an option off the status tray icon to re-establish the xpra connection.

[Antoine Martin]

Two options I can think of:

• it execs itself using the command line found in sys.argv
  • easier / should be simple to do
• we pass the socket factory to the client class so it can re-create it
  • more difficult / potentially more bugs, but also a better approach..

[migration script]

this ticket has been moved to: ​https://github.com/Xpra-org/xpra/issues/81