Add sentence about SE research overview

[jpthiele]

This nicely mirrors the sentence about domain research and fixes #260 apart from mentioning `unknown unknowns' somewhere.

But I think that might fit somewhere more general and I'm open for ideas there.

[CaptainSifff]

some spots where you could add sth. would be:

• the master program
• Kay's CV
• You can extend the leadership roles. to know what happens in CS.