Motivation:
Request bodies can easily be larger than Integer.MAX_VALUE in practice.
There's no reason, or intention, for Netty to impose this artificial constraint.
Worse, it currently does not fail if the body is larger than this value;
it just silently only reads the first Integer.MAX_VALUE bytes and discards the rest.
This restriction doesn't effect chunked transfers, with no Content-Length header.
Modifications:
Force the use of `long HttpUtil.getContentLength(HttpMessage, long)` instead of
`long HttpUtil.getContentLength(HttpMessage, long)`.
Result:
Netty will support HTTP request bodies of up to Long.MAX_VALUE length.