In case of make bucket, there is a chance of Transfer-Encoding is sent
where Content-Length is missing. This patch fixes the problem by
checking whether Transfer-Encoding: chunked is set along with
Content-Length.
Do not look for Content-Length in headers and try to convert them into
integer representations use ContentLength field from *http.Request*.
If Content-Length is understood to be as '-1' then treat it as an error
condition, since it could be a malformed body to crash the server.
Fixes#1011
