function gzipSync(data, opts) {
    if (!opts)
        opts = {};
    var c = crc(), l = data.length;
    c.p(data);
    var d = dopt(data, opts, gzhl(opts), 8), s = d.length;
    return gzh(d, opts), wbytes(d, s - 8, c.d()), wbytes(d, s - 4, l), d;
}
Compresses data with GZIP
@param data The data to compress
@param opts The compression options
@returns The gzipped version of the data