Allow setting NetworkTables IP address as well as team number

[PeterJohnson]

When running robot code on a desktop in simulation mode, the NetworkTables server is not running at a team-type address (e.g. roborio-TEAM-frc.local or 10.TE.AM.2) but rather at the desktop IP address. For testing with robot desktop simulation, it would be helpful to be able to set the IP address, not just the team number, on the frcvision web server, and have both the default vision program and the example programs work in this mode.