Added __on_player_message event (#1312)

* Added __on_player_sends_message event

* Docs for chat message event

* Rename to __on_player_message

* Editor support

* Added event to event_test app

* Update docs/scarpet/api/Events.md

Co-authored-by: gnembon <41132274+gnembon@users.noreply.github.com>

src/main/resources/assets/carpet/scripts/event_test.sc

@@ -251,6 +251,13 @@ __on_player_disconnects(player, reason) ->
     print('Player '+player+' disconnects because: '+reason)
 );
 
+__on_player_message(player, message) ->
+(
+    print('');
+    print('__on_player_message(player, message)');
+    print('Player '+player+' sent message: '+message)
+);
+
 __on_player_chooses_recipe(player, recipe, full_stack) ->
 (
     print('');