Simplify the cmd/http package overall by removing
custom plain text v/s tls connection detection, by
migrating to go1.12 and choose minimum version
to be go1.12
Also remove all the vendored deps, since they
are not useful anymore.
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
Harshavardhana