Raise CMake requirement to 3.0+

FindPythonLibs.cmake from CMake 2.8.x is not capable of finding Python
libraries on Maui, updating to CMake 3.x solves the problem.

Looks like it is better crafted.

Other parties interested in Calamares should already have CMake 3.x
so this is not a problem.
Fix autologin in displaymanager module
Requires boost-devel >= 1.54.0

This is what Calamares currently requires.

[rpm] Bump boost-devel version requirement to 1.54.0+
Don't use KF5 macros and remove e-c-m bdep

Calamares doesn't use e-c-m.

[rpm] Don't use KF5 macros and remove e-c-m bdep
Merge branch 'calamares'