ℹ Improve docs and documentation (again)

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

lib/mobilizon_web/api/comments.ex

@@ -58,7 +58,7 @@ defmodule MobilizonWeb.API.Comments do
   @spec get_in_reply_to_comment(nil) :: nil
   defp get_in_reply_to_comment(nil), do: nil
   @spec get_in_reply_to_comment(String.t()) :: Comment.t()
-  defp get_in_reply_to_comment(inReplyToCommentURL) do
-    ActivityPub.fetch_object_from_url(inReplyToCommentURL)
+  defp get_in_reply_to_comment(in_reply_to_comment_url) do
+    ActivityPub.fetch_object_from_url(in_reply_to_comment_url)
   end
 end

lib/mobilizon_web/api/events.ex

@@ -9,6 +9,9 @@ defmodule MobilizonWeb.API.Events do
   alias Mobilizon.Service.ActivityPub.Utils, as: ActivityPubUtils
   import MobilizonWeb.API.Utils
 
+  @doc """
+  Create an event
+  """
   @spec create_event(map()) :: {:ok, Activity.t()} | any()
   def create_event(
         %{

lib/mobilizon_web/api/groups.ex

@@ -9,6 +9,9 @@ defmodule MobilizonWeb.API.Groups do
   alias Mobilizon.Service.ActivityPub.Utils, as: ActivityPubUtils
   import MobilizonWeb.API.Utils
 
+  @doc """
+  Create a group
+  """
   @spec create_group(map()) :: {:ok, Activity.t()} | any()
   def create_group(
         %{