Install nodejs for RHEL/Fedora

nodejs is required for Horizon (ships a copy of lessc internally).  I
couldn't find nodejs in the rpm list, despite it being installed in
lib/horizon.  This adds to the rpm list as NOPRIME and retains the old
install point.

RHEL6 has nodejs in EPEL now, so we remove the old hack that installed
an upstream version and add it to the install mentioned previously

Change-Id: Ib3ee2f7d77e22666c9055c8528288c01b46a95d3
diff --git a/files/rpms/horizon b/files/rpms/horizon
index 151e7e2..cf16cdb 100644
--- a/files/rpms/horizon
+++ b/files/rpms/horizon
@@ -3,6 +3,7 @@
 gcc
 httpd # NOPRIME
 mod_wsgi  # NOPRIME
+nodejs # NOPRIME
 pylint
 python-anyjson
 python-BeautifulSoup