Eos selection

Update the parameter file selection of EoS to allow individual selection, and add checks to give helpful error messages instead of seg faults if the code tries to use a non-enabled EoS.

Update planetary example and docs with this and other small bits and pieces.

Closes #743 (closed)

doc/RTD/source/ParameterFiles/parameter_description.rst

@@ -909,15 +909,10 @@ The ``EoS`` section contains options for the equations of state.
 Multiple EoS can be used for :ref:`planetary`,
 see :ref:`planetary_eos` for more information. 
 
-To enable one or multiple of these EoS, the corresponding ``planetary_use_*:``
+To enable one or multiple EoS, the corresponding ``planetary_use_*:``
 flag(s) must be set to ``1`` in the parameter file for a simulation,
-along with the path to any table files, which are provided with the 
+along with the path to any table files, which are set by the 
 ``planetary_*_table_file:`` parameters.
-This currently means that all EoS within each base type are prepared at once, 
-which we intend to simplify in the future.
-
-The data files for the tabulated EoS can be downloaded using 
-the ``examples/EoSTables/get_eos_tables.sh`` script.
 
 For the (non-planetary) isothermal EoS, the ``isothermal_internal_energy:``
 parameter sets the thermal energy per unit mass.