immovable_help.lua
------------------

This script returns a formatted entry for the in-game immovable help (Tribal Encyclopedia).
Pass the internal tribe name and immovable name to the coroutine to select the
immovable type.

.. function:: immovable_help_string(tribe, immovable_description)

   Displays the immovable with a helptext.

   :arg tribe: the tribe that we are displaying this help for; the same immovable
      can be used by various tribes in different ways.
   :type tribe: :class:`LuaTribeDescription`

   :arg immovable_description: the immovable_description that the help is
      being displayed for.
   :type immovable_description: :class:`LuaImmovableDescription`

   :returns: Help string for the immovable