populate:users should create an admin user (doubleunion#796)

When creating fake users for a development configuration, create an
admin user that can be used for testing admin tools.

lib/tasks/populate.rake

@@ -1,18 +1,28 @@
+def create_fake_user(state = nil)
+  unless state
+    states = User.state_machine.states.map(&:name).map(&:to_s)
+    state = states.sample
+  end
+
+  user = User.new
+
+  user.username = Faker::Internet.user_name
+  user.name = Faker::Name.name
+  user.email = Faker::Internet.email
+  user.state = state
+
+  return user
+end
+
 namespace :populate do
   desc "Populate users in development"
   task users: :environment do
     raise "development only" unless Rails.env.development?
 
-    10.times do
-      states = User.state_machine.states.map(&:name).map(&:to_s)
-
-      user = User.new
-
-      user.username = Faker::Internet.user_name
-      user.name = Faker::Name.name
-      user.email = Faker::Internet.email
-      user.state = states.sample
+    created_admin = false
 
+    10.times do
+      user = create_fake_user
       user.save
 
       # Some parts of the app expect members to have an application with a valid processed_at date.
@@ -21,7 +31,12 @@ namespace :populate do
         user.save!
       end
     end
+
+    admin_user = create_fake_user("voting_member")
+    admin_user.make_admin!
+    admin_user.save
   end
+
   task :user, [:username, :name, :email, :state] => :environment do |t, args|
     raise "username not provided" unless !!args.username && !args.username.empty?