Function serialize_zone_assignments

plugins/preserve-rooms.cpp:127–134

}

static string serialize_zone_assignments(const ZoneAssignments & data) {
    vector<string> elems;
    for (auto elem : data) {
        vector<int32_t> ints = {elem.first, elem.second.first, elem.second.second};
        elems.push_back(join_strings("/", ints));
    }
    return join_strings(",", elems);
}

static void store_zone_assignments(const ZoneAssignments & data, const char * suffix) {
    get_config(suffix, true).set_str(serialize_zone_assignments(data));