Hrvoje Senjan authored Jun 10, 2014 and Martin Flöser committed Jun 16, 2014

This servers two purposes.
1. it makes KWin/5 co-installable with KWin/4 as now binary and
   all libraries etc. are renamed or installed to a different
   location.
2. In future we need a dedicated X11 and Wayland main function
   anyway. Thus it makes most sense to rename to kwin_x11 directly
   instead of first renaming to kwin5. The reason why we need to
   have dedicated main functions is that kwin needs to check early
   whether X11 is working or Wayland is working. Right now the first
   thing kwin does is trying to connect to the XServer. This happens
   before the QApplication is constructed and before command line
   args are processed. On Wayland we won't want to test whether we
   can connect to the XServer. As it's too early to check whether we
   are starting kwin for X11 or Wayland the most convenient way is to
   have dedicated binaries - thus a rename is needed. Just renaming
   kwin for wayland is also not a good idea as in future the "main"
   kwin will be...