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.

mk/git.mk

@@ -0,0 +1,8 @@
+_GITVER_SH=	if git rev-parse --short HEAD >/dev/null 2>&1; then \
+			printf "."; \
+			git rev-parse --short HEAD; \
+		else \
+			echo ""; \
+		fi
+_GITVER!=	${_GITVER_SH}
+GITVER=		${_GITVER}$(shell ${_GITVER_SH})