Changing the default quality level

[daxpedda]

At the moment the default quality level when encoding is 11, when using BrotliEncoderParams::default(), see source.

I was wondering if there is any interest in changing the default to something more reasonable, as 11 is the highest and takes an extremely long time.

[JorritSalverda]

Cloudflare found level 4 to offer the best balance between compression and speed: https://blog.cloudflare.com/this-is-brotli-from-origin#brotli-compression-to-11. Any chance this can get updated in this crate?