Fix blank content-encoding headers
Fix blank content-encoding headers

The S3 docs claim that you should set the content-encoding to aws-chunked
for a streaming upload. This however results in S3 serving files with a blank
content-encoding header. After discussion with AWS support, it appears
that setting the content-encoding to aws-chunked isn't actually necessary
since S3 can infer this from other headers present in the request

alexshepherd-hydrant/fog-aws,nomadium/fog-aws,nilroy/fog-aws,backupify/fog-aws,fog/fog-aws,puneetloya/fog-aws,nomadium/fog-aws,bahchis/fog-aws,tdg5/fog-aws,engineyard/fog-aws,alexshepherd-hydrant/fog-aws,ming-relax/fog-aws,tdg5/fog-aws,gswallow/fog-aws,puneetloya/fog-aws,engineyard/fog-aws,ming-relax/fog-aws,ehowe/fog-aws,esthervillars/fog-aws,nalabjp/fog-aws,bahchis/fog-aws,esthervillars/fog-aws,backupify/fog-aws,fog/fog-aws,fog/fog-aws,ehowe/fog-aws,gswallow/fog-aws,nalabjp/fog-aws,nilroy/fog-aws