Get config and display/hide register button

lib/mobilizon/common-config.ex

@@ -1,7 +1,20 @@
 defmodule Mobilizon.CommonConfig do
-  def registrations_open?(), do: instance_config() |> get_in([:registrations_open])
+  @moduledoc """
+  Instance configuration wrapper
+  """
 
-  def instance_name(), do: instance_config() |> get_in([:name])
+  def registrations_open?() do
+    instance_config()
+    |> get_in([:registrations_open])
+    |> to_bool
+  end
+
+  def instance_name() do
+    instance_config()
+    |> get_in([:name])
+  end
 
   defp instance_config(), do: Application.get_env(:mobilizon, :instance)
+
+  defp to_bool(v), do: v == true or v == "true" or v == "True"
 end