Install nodejs-less from EPEL

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