fix for the root cause of
issue #434 (previous pages being visible in the background)
rollback of
r08642c7da4a3b5e05be51a8b45995e799bbc4bbf ("add DLC button to net game room")
missed this one when fixing regular flakes.
issue #444
add gsoc students. also sphrix to translators
countless small optimisation for cmake, output messages are now coherent (mostly) and the options get fully respected (eg. skipping library search if not activated)
Ok. Seems to me if you disconnect on any page, you should go to the main net page, since presumably you were in some part of net play. I think this should avoid ending up in a "lobby" after disconnecting