Change properties and logs dirs from "perunv3" to "perun"

- change the path in main pom.xml file
- change the path in core for getPropertyFromConfiguration (Utils)
- change the path in rpc-lib for getPropertyFromConfiguration

NEED to be done, before apply this commit:
- create dir /etc/perun with same rights like /etc/perunv3
- create dir /var/log/perun with same rights like /var/log/perunv3
- change /home/perun/tomcat-devel/bin/setenv.sh parameter for
	log4j.properties file to /etc/perun if it's hardcoded here