MineTest custom death_formspec CSM

Modified death_formspec which tell death coordinates and adds ghost mode and leave to menu buttons
Installation:

• /!\Ensure that enable_client_modding = true in settings(minetest.conf)
• Install this mod in minetest's clientmods directory and add load_mod_cdf = true to clientmods/mods.conf
  *Ghost mode allows you to grab stuff from your bones then respawn and stuff will kept