Add C-linkage wrapper for colvarscript (useful with ctypes)

{

}

extern "C" {

  // Generic hooks; NAMD and VMD have Tcl-specific versions in the respective proxies

  int run_colvarscript_command(int argc, const char **argv)

  {

    colvarproxy *cvp = cvm::proxy;

    if (!cvp) {

      return -1;

    }

    if (!cvp->script) {

      cvm::error("Called run_colvarscript_command without a script object initialized.\n");

      return -1;

    }

    return cvp->script->run(argc, argv);

  }

  const char * get_colvarscript_result()

  {

    colvarproxy *cvp = cvm::proxy;

    if (!cvp->script) {

      cvm::error("Called run_colvarscript_command without a script object initialized.\n");

      return "";

    }

    return cvp->script->result.c_str();

  }

}

/// Run method based on given arguments

int colvarscript::run(int argc, char const *argv[]) {