ECM dependency

[David Faure]

Please update extra-cmake-modules, otherwise KF5 won't compile.

I changed QT_NO_KEYWORDS to QT_NO_SIGNALS_SLOTS_KEYWORDS
so that we can keep using emit and foreach in .cpp files, these don't hurt.

But that means I cleaned stuff up, so you need an up-to-date ECM, otherwise 
things will break.

-- 
David Faure, faure at kde.org, http://www.davidfaure.fr
Working on KDE, in particular KDE Frameworks 5