Correct some spelling mistakes

Automaticaly --> Automatically
Invalide --> Invalid
Strech --> Stretch
allows to --> allows one to
attachement --> attachment
contraints --> constraints
inconsistant --> inconsistent
occured --> occurred
occurences --> occurrences
permits to --> permits one to
postion --> position
regularily --> regularly
transfered --> transferred

src/buttons.c

@@ -2198,7 +2198,7 @@ void Button_Resolution(int btn)
         Video_mode[selected_mode].Fullscreen,
         chosen_pixel))
     {
-      Error(0); // On signale à l'utilisateur que c'est un mode invalide
+      Error(0); // Tell user it is an invalid mode
       Pixel_ratio=PIXEL_SIMPLE;
       Init_mode_video(
         Video_mode[Current_resolution].Width,