Add ability to provide help to different users in parallel
Currently it is not possible to provide help to different users at the same time: clients can only do SSH port forwarding on port 5900 of the server.
Maybe it could be possible to tweak the system to permit this:
- by fixing #1
- by configuring the SSH server to allow port forwarding on a pool of ports
- by modifying the client so that it tries successively each ports of the pool until it finds one that is free (I suppose SSH server or client returns a string like "port already in use" which could be parsed)
- by indicating this chosen port to the helper (either with a server script that monitor port usage or by printing it on the client)
There is still (at least) the password issue: after a helper gave a password to the person he want to help, the SSH connection must be established before the password is changed or deactivated by another helper.