Here is a patch with the following changes:

* Clarified that wbits affects the container format as well as windows size
* Undid some word wrapping to make the diff simpler
* Added zero and 32 + n for decompression
* Added full list of options under decompressobj(), and link decompress() to that. Otherwise we end up saying decompression generates a header, when it really parses the header.
* Added tests for various wbits values
* Compressing with window bits = 8 not actually supported (Zlib bumps it to 9: <https://github.com/madler/zlib/commit/8e34b3a#diff-8940271ef2146523af486ca4408361daR264>. The change log says “Force windowBits > 8 to avoid a bug in the encoder for a window size of 256 bytes”.)
* Updated doc strings