adds support for automatically decompressing gzip/deflate data received

[mogorman]

adds support for automatically decompressing gzip/deflate data received unless told not to in the options with raw: true

[mogorman]

I think it works better this way automatically, but could be done in reverse, so you have to manually say you want it uncompressed.

given though you have to add the accept-encoding flag already, I think most people would prefer it this way.

[mogorman]

Also curious what would be the right way to add meaningful unit test for this