fixes issue with creating new organizations when there are no ip pools

app/models/organization.rb

@@ -48,7 +48,9 @@ class Organization < ApplicationRecord
   has_many :ip_pool_rules, :dependent => :destroy, :as => :owner
 
   after_create do
-    self.ip_pools << IPPool.transactional.default
+    if pool = IPPool.transactional.default
+      self.ip_pools << IPPool.transactional.default
+    end
   end
 
   def status

db/seeds.rb

@@ -3,4 +3,4 @@ user = User.create!(:first_name => "Example", :last_name => "Admin", :email_addr
 org = Organization.create!(:name => "Acme Inc", :permalink => "acme", :time_zone => "London", :owner => user)
 org.users << user
 
-server = Server.create!(:ip_pool => ip_pool, :organization => org, :name => "Example Server", :permalink => "example", :mode => "Live")
+server = Server.create!(:organization => org, :name => "Example Server", :permalink => "example", :mode => "Live")