Fix undefined method `[]' for nil:NilClass for Network installation

Add default OpenStack Network installation service_type name to avoid
undefined method error.

Fixes bug #1281922

Change-Id: I40176cd3b826965fef7292e13279c9f3d7324ded

README.md

@@ -26,6 +26,12 @@ Note that all attributes are in the `default["openstack"]` "namespace"
 
 * `openstack['api']['auth']['version']` - Select v2.0 or v3.0. Default v2.0. The default auth API version used by other components to interact with identity service.
 
+default
+-------
+
+Support multiple network types. Default network type is "nova" with the other option supported being "neutron".
+The attribute is in the `default["openstack"]["compute"]["network"]["service_type"]`.
+
 Recipes
 =======
 

attributes/default.rb

@@ -287,6 +287,9 @@ default['openstack']['sysctl']['net.ipv4.conf.default.rp_filter'] = 0
 # Default Ceph settings
 default['openstack']['ceph']['key-url'] = 'https://ceph.com/git/?p=ceph.git;a=blob_plain;f=keys/release.asc'
 
+# Default OpenStack Network Type: nova (optional: neutron)
+default['openstack']['compute']['network']['service_type'] = 'nova'
+
 case platform
 when 'ubuntu'
   default['openstack']['ceph']['platform']['uri'] = 'http://ceph.com/debian-emperor'