Make the JSON file and elements path overrideable in instack-install-undercloud-packages

scripts/instack-install-undercloud-packages

@@ -10,6 +10,12 @@ exec 2>&1
 
 echo "Running $0"
 
+export JSONFILE=${JSONFILE:-/usr/share/instack-undercloud/json-files/fedora-20-undercloud-packages.json}
+
+export ELEMENTS_PATH=${ELEMENTS_PATH:-"/usr/share/diskimage-builder/elements/ \
+                                       /usr/share/tripleo-image-elements/ \
+                                       /usr/share/instack-undercloud/"}
+
 # generate ssh authentication keys if they don't exist
 if [ ! -f ~/.ssh/id_rsa ]; then
   echo "Generating an ssh key..."
@@ -43,10 +49,8 @@ export UNDERCLOUD_NOVA_PASSWORD=${UNDERCLOUD_NOVA_PASSWORD:-$(tripleo os-make-pa
 export UNDERCLOUD_IRONIC_PASSWORD=${UNDERCLOUD_IRONIC_PASSWORD:-$(tripleo os-make-password)}
 
 sudo -E instack \
-  -p /usr/share/diskimage-builder/elements/ \
-     /usr/share/tripleo-image-elements/ \
-     /usr/share/instack-undercloud/ \
-  -j /usr/share/instack-undercloud/json-files/fedora-20-undercloud-packages.json
+  -p $ELEMENTS_PATH \
+  -j $JSONFILE
 
 sudo os-refresh-config