Add vector-valued options to the config file
This change modifeis Options.hpp to add the possibility of vector-valued options to the config file and command line. From the 'case' code, this option is used by (for example) std::vector<int> intvec; add_option("Name",&intvec,"Description); When run, options of the form --Name 1 2 3 4 (at the command line) or Name = 1 2 3 4 (in the config file) will be added to the vector 'intvec' as separate entries. Because add_option is a template function, this works identically for double (floating point)-valued options. It has not been tested with string options. Since an empty vector is a perfectly cromulent and unambiguous possibility, vector-valued options do *not* permit the specification of defaults.