It can happen with erroneous clients which do not send `Host:`
header until 4k worth of header bytes have been read. This can lead
to Peek() method of bufio to fail with ErrBufferFull.
To avoid this we should make sure that Peek buffer is as large as
our maxHeaderBytes count.
* Refactor HTTP server to address bugs
* Remove unnecessary goroutine to start multiple TCP listeners.
* HTTP server waits for shutdown to maximum of Server.ShutdownTimeout
than per serverShutdownPoll.
* Handles new connection errors properly.
* Handles read and write timeout properly.
* Handles error on start of HTTP server properly by exiting minio
process.
Fixes#4494#4476 & fixed review comments