Add admin dashboard, event reporting, moderation report screens, moderation log

Close #156 and #158

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/statistics.ex

@@ -0,0 +1,31 @@
+defmodule Mobilizon.Service.Statistics do
+  @moduledoc """
+  A module that provides cached statistics
+  """
+  alias Mobilizon.Events
+  alias Mobilizon.Users
+
+  def get_cached_value(key) do
+    case Cachex.fetch(:statistics, key, fn key ->
+           case create_cache(key) do
+             value when not is_nil(value) -> {:commit, value}
+             err -> {:ignore, err}
+           end
+         end) do
+      {status, value} when status in [:ok, :commit] -> value
+      _err -> nil
+    end
+  end
+
+  defp create_cache(:local_users) do
+    Users.count_users()
+  end
+
+  defp create_cache(:local_events) do
+    Events.count_local_events()
+  end
+
+  defp create_cache(:local_comments) do
+    Events.count_local_comments()
+  end
+end