Jiggered solution to launch 2 connected instances

Configuration file is now specified as the first (and only) commandline
argument.

config.txt has been renamed configserver.txt because it's a server
configuration. It has been otherwise unchanged.

New file: configclient. isServer: 0, and serverIP: 127.0.0.1

Waves project set to launch with configserver.txt
(properties->Debugging->CommandArguments)

New project: ClientInstance. It's totally empty. Project Properties are
jigged to launch the Waves executable from the Waves working directory,
using configclient.txt config. Also configured not to build ever, because
building empty projects fails.
Jiggered properties were Command and Working Directory in Debugging.

Jigged solution to launch both ClientInstance and Waves simultaneously on
F5. Solution Properties->Common Properties->Startup Project->Multiple
Startup Projects

Issues outstanding:

Stupid not-actually-a-window means both instances just run on top of each
other, and you have to alt-tab to see what's on the other instance.

Menu requires key input on both instances, which is annoying

Both windows don't close together. Not really a bug. But it means you
can't use the "stop debugging" command to close the client. You could try
setting both client and server to launch with debugging in the solution
startup projects, but I thought it'd be a little weird to have both
projects debugging at the same time.