TODO

Make all internal members start with m_* instead of _*

Compile on Windows.

Some complex types to think about: 
X0 can be either a NOMAD::Point or a filename
std::list<std::string> DISPLAY_STATS
int[2] LH_SEARCH
etc. This is one reason to use strings in ParamValue.

Format of the default parameters file:
Maybe using a format like XML (or JSON, but XML seems better suited in this case), would
help for the default parameter file. See TinyXML-2 as a library for parsing XML. It is
lightweight, easy to use, and does the minimum, which is what we need.
Format should include:
Parameter description for help output (see NOMAD_3 - Parameters.cpp - help())
If the parameter is basic / advanced / developer (ibidem)
Is the value required or not.
Such a format would potentially be easier to parse, in particular for parameter
description. We would still have to determine how to write a parameter that can
have multiple types.