Move non compiled libraries from /lib/rc to /libexec/rc

OpenRC version is now stored as plaintext in /libexec/rc/version

Plugins (cursplash, splashutils) will have to be re-compiled to pickup
the new directories. State data needs to be moved from /lib/rc/init.d
to /libexec/rc/init.d as well.

net/Makefile

@@ -1,4 +1,4 @@
-DIR=	${PREFIX}/${RC_LIB}/net
+DIR=	${LIBEXECDIR}/net
 SRCS=	ifconfig.sh.in
 INC=	dhclient.sh dhcpcd.sh ifconfig.sh macchanger.sh macnet.sh \
 	ssidnet.sh system.sh wpa_supplicant.sh