Built-in way to cache the parameters

[lifthrasiir]

Currently compression parameters have to be manually copied from the search result, but it would be great to have an official method to save that. This would require a sort of the configure-from-file option, or we can combine it with the cache output file so that using the same cache parameter will automatically read and write the cache. It is best to have the same feature also in the API, but I'm not sure I can make it work without sacrificing non-Node.js uses.