Allow rocket ports to supply the interior without a cargo module

[Yobbo]

I was a bit confused when i constructed some rocket ports and intake/outlet fittings, then they did nothing at all. Turns out they both only work with cargo modules. It's pretty overblown that i have to build a gas cargo module just to vent and resupply the oxygen in my piloting module. Then i have to build a liquid cargo module to flush the toilets.

It would be nice if rocket ports would supply the intake / outlets in the rocket interior without the need for any intermediary.