Add default connection for autoconfigured server, Fix async texture readback

[tribal-tec]

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[tribal-tec]

FYI: @jafyvilla

[eile]

single-node autoconfigs had no listening ports for security considerations. Can we make the add connection conditional on a ConfigParam?

[tribal-tec]

Which security considerations? If one launches a eqPly default w/o any config, one cannot use the shipped 'feature' of adding windows on-the-fly. That seems more pressing to me, but I can be convinced otherwise.

[eile]

Of having an open TCP port (with no input validation) in a desktop application. Maybe we can open the admin connection through a anon pipe somehow?

Edit: Having the app open it explicitly through ConfigParams seemed like a smaller evil, although I think it should be some process-local communication for the admin stuff.

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[tribal-tec]

Retest this please

[bbpbuildbot]

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