since we still support g++-7, where filesystem is marked experimental,
we introduce a wrapper header and expose the namespace to use
as Opm::filesystem.
for gcc we unconditionally link with libstdc++fs in the python bindings.
the setup.py stuff links as c code, not c++ code, so it is not
automatically added on any gcc version. this might prove unportable
later.
Differentiate between the input type, as specified in the json configuration
file, and the internal native type used to store data. This is a many-to-one
mapping, where e.g. both the input types STRING and RAW_STRING map to the
internal datatype std::string.
Additional changes:
- Have removed several ParserItem() constructors.
- The size_type::SINGLE is default for a ParserItem, and not set explicitly in
the generated ParserKeywords.cpp file.
- Have removed a call to boost::lexical_cast<> - just use std::to_string()
