private byte[] toByteArray(ChannelBuffer content) {
		if (content.hasArray()) {
			return content.array();
		}
		else {
			byte[] bytes = new byte[content.readableBytes()];
			content.getBytes(0, bytes);
			return bytes;
		}
	}
Message converter (inbound only) to convert a Netty Http MessageEvent to
a Message. Returns null if the content is not readable.

@author Mark Fisher
@author Jennifer Hickey
@author Gary Russell
@author Marius Bogoevici
@author Peter Rietzler
extensions/spring-xd-extension-http/src/main/java/org/springframework/integration/x/http/NettyInboundMessageConverter.java