Add a progress bar for ADD <url> <dst>

Signed-off-by: Victor Vieux <vieux@docker.com>
Merge pull request #7315 from vieux/add_pb

add progress bar to ADD
move some io related utils to pkg/ioutils

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
pkg/ioutils: add WriteCloserWrapper

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
pkg/ioutils: add NewBufReaderWithDrainbufAndBuffer

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
pkg/ioutils: add ReaderErrWrapper to readers

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
pkg/pool: add pools for bufio readers & writers

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
archive: use pooled bufio readers and writers

Docker-DCO-1.1-Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com> (github: unclejack)
Merge pull request #7542 from unclejack/refactor_archive_buffering

Refactor archive buffering