After discussion among developers we settled on the Mozilla style
with a few tweaks:

* Do not align operator arguments.

* Do not always break after a function return type.

* Limit to 79 columns instead of 80 to fit edge cases
  better in 80-column terminals as CMake has always done.

* Format for C++98 instead of C++11 because CMake is written
  in the former language.

Co-Author: Daniel Pfeifer <daniel@pfeifer-mail.de>