Allow to use external nodegenerator

  * Switch to downstream reclass
  * Add reference replacement in generator:
   COLON_SYMBOL_FOR_FUTURE_REFERENCE => ':'

https://mirantis.jira.com/browse/PROD-30702

Change-Id: I342e2e3abc770f3a150668df06cc06fe0f3e2687
diff --git a/.kitchen.yml b/.kitchen.yml
index 1c7b65f..24be116 100644
--- a/.kitchen.yml
+++ b/.kitchen.yml
@@ -24,7 +24,8 @@
         "*":
           - reclass
   init_environment: |
-        sudo yum install -y python-netaddr || sudo apt-get install -y python-netaddr || true
+        sudo apt-get install -y python-netaddr python-pip || true
+        sudo pip install git+http://gerrit.mcp.mirantis.com/packaging/sources/reclass@mcp/xenial/extra
 
 verifier:
   name: inspec