Adjust path to the default configuration file
Adjust the mm2_update-mirrorlist-server

No need to use MM_DIR (script is now in /usr/bin)
No need to specify the configuration file (the default one is fine)
Rework the spec file to add missing folders and create them all in one place
Adjust the default configuration file to use to be /etc/mirrormanger/mirrormanger2.cfg

While at it, adjust the documentation and some small coding style changes