Feat/local params

[seanpearsonuk]

• classes to set up a parametric study locally, i.e. in PyFluent without running Fluent. Knowledge of parameters comes directly from a case file
• functionality to execute the locally defined parametric study in parallel. This uses the existing parametric classes
• a Fluent case reader to facilitate the local parametric study. Here temporarily - see PR in core repository. Eventually to a separate repo?
• lispy.py. This provides a Scheme parser, copied from the web. It was necessary to make a few adjustments. Null / empty list triggered an exception, while (1 . 2) was interpreted as [1, '.', 2], for which I generate [1, 2]. This will also move.
• changes in the core parametric classes. Removed static data from the study class to allow multiple non-interfering sessions.

[seanpearsonuk]

@tejalprabhu01 I have added you here to check that these change don't break optiSLang->PyFluent.

[tejalprabhu01]

@tejalprabhu01 I have added you here to check that these change don't break optiSLang->PyFluent.

@seanpearsonuk I have reviewed the changes. Nothing breaks on optiSLang side. Thanks.