Enhancement: Add MIP solvers extra flags in --help

[raphaelboudreault]

Hi, I am currently using MiniZinc with the SCIP solver. In the MiniZinc IDE, I am able to see the different "Extra configuration parameters" available for SCIP in the configuration editor. However, in the command line, using minizinc --help scip only shows the MiniZinc driver options and the SCIP MIP wrapper options. Would it be also possible to see the extra solver options with their description? Thanks!