ENH: Added new abaqus coordSet writer

Write coordSet(s) as Abaqus point fields

Example usage

    T
    {
        type        sets;
        setFormat   abaqus;
        fields      (T);
        sets
        {
            ...
        }
    }
    \endverbatim

    Optional format options
    \verbatim
    formatOptions
    {
        abaqus
        {
            format          ascii;

            // Optional entries

            // Custom header: $ entries are substituions
            header
            (
                "** OpenFOAM abaqus output"
                "** Project $FOAM_CASE"
                "** File $FILE_NAME"
                "** $FIELD_NAME Time t=$TIME"
            );

            // Write geometry in addition to field data
            writeGeometry   yes;

            // Null value when sample value is not found
            // Default is scalar::min
            nullValue       0;

            // Insert additional time sub-directory in the output path
            // - yes : postProcessing/<fo-name>/<time>/<file>
            // - no  : postProcessing/<fo-name>/<file>
            useTimeDir      no;

            // Available when 'useTimeDir' is 'no' to disambiguate file names

            // Time base for output file names:
            // - 'time'      : <base>.inp_<field>.<time>
            // - 'iteration' : <base>.inp_<field>.<iteration>
            timeBase        iteration;

            // Optional start counters when using timeBase iteration
            writeIndex
            (
                T 1
            );

            ...
        }
    }