Function token_to_enum_val

plugins/stockpiles/StockpileSerializer.cpp:218–223

 */
template <typename E>
static typename df::enum_traits<E>::base_type token_to_enum_val(const string& token) {
    E val;
    if (!find_enum_item(&val, token))
        return -1;
    return val;
}

static bool matches_filter(color_ostream& out, const vector<string>& filters, const string& name) {
    for (auto & filter : filters) {