Add EPEL-7 repo for RHEL7

* RHEL7 requires epel for many dependencies.
* The default RDO URL also switched to an icehouse version.
* RHEL6 RDO repo also will be configured for RHEL7, but the
  configuration variable name remains RHEL6_RDO_REPO_RPM for compatibility
  reasons.

Change-Id: I414c0f5357bf24c8d5657ea8231515461862e734
diff --git a/stack.sh b/stack.sh
index 983a6bf..8ac0134 100755
--- a/stack.sh
+++ b/stack.sh
@@ -215,21 +215,24 @@
     apt_get install --force-yes gplhost-archive-keyring
 fi
 
-if [[ is_fedora && $DISTRO =~ (rhel6) ]]; then
-    # Installing Open vSwitch on RHEL6 requires enabling the RDO repo.
-    RHEL6_RDO_REPO_RPM=${RHEL6_RDO_REPO_RPM:-"http://rdo.fedorapeople.org/openstack-havana/rdo-release-havana.rpm"}
-    RHEL6_RDO_REPO_ID=${RHEL6_RDO_REPO_ID:-"openstack-havana"}
+if [[ is_fedora && $DISTRO =~ (rhel) ]]; then
+    # Installing Open vSwitch on RHEL requires enabling the RDO repo.
+    RHEL6_RDO_REPO_RPM=${RHEL6_RDO_REPO_RPM:-"http://rdo.fedorapeople.org/openstack-icehouse/rdo-release-icehouse.rpm"}
+    RHEL6_RDO_REPO_ID=${RHEL6_RDO_REPO_ID:-"openstack-icehouse"}
     if ! sudo yum repolist enabled $RHEL6_RDO_REPO_ID | grep -q $RHEL6_RDO_REPO_ID; then
         echo "RDO repo not detected; installing"
         yum_install $RHEL6_RDO_REPO_RPM || \
             die $LINENO "Error installing RDO repo, cannot continue"
     fi
-
-    # RHEL6 requires EPEL for many Open Stack dependencies
-    RHEL6_EPEL_RPM=${RHEL6_EPEL_RPM:-"http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm"}
+    # RHEL requires EPEL for many Open Stack dependencies
+    if [[ $DISTRO =~ (rhel7) ]]; then
+        EPEL_RPM=${RHEL7_EPEL_RPM:-"http://dl.fedoraproject.org/pub/epel/beta/7/x86_64/epel-release-7-0.1.noarch.rpm"}
+    else
+        EPEL_RPM=${RHEL6_EPEL_RPM:-"http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm"}
+    fi
     if ! sudo yum repolist enabled epel | grep -q 'epel'; then
         echo "EPEL not detected; installing"
-        yum_install ${RHEL6_EPEL_RPM} || \
+        yum_install ${EPEL_RPM} || \
             die $LINENO "Error installing EPEL repo, cannot continue"
     fi