worker_help.lua
---------------

This script returns a formatted entry for the ingame worker help.
Pass the internal tribe name and worker name to the coroutine to select the
worker type.

.. function:: worker_help_producers_string(worker_description)

   Displays the buildings that can produce the worker

   :arg tribe: the worker's tribe from C++.
   :arg worker_description: the worker_description from C++.
   :returns: Info about buildings that produce this worker


.. function:: worker_help_employers_string(worker_description)

   Displays the buildings where the worker can work

   :arg worker_description: the worker_description from C++.
   :returns: Info about buildings that use this worker


.. function:: worker_help_string(worker_description)

   Displays the worker with a helptext, an image and the tool used

   :arg tribe: The :class:`LuaTribeDescription` for the tribe
               that we are displaying this help for.