daemon logging: unifying output and timestamps

A little refactor of the ./pkg/log so engine can have a logger instance

Signed-off-by: Vincent Batts <vbatts@redhat.com>
Minor changes to SSHd example

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)
Link directly to the 'latest' release alias

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Fix commit api document

The commit message field should be `comment`, not `m`
https://github.com/docker/docker/blob/master/api/server/server.go#L478

Signed-off-by: Huayi Zhang <irachex@gmail.com>
Merge pull request #8516 from jamtur01/sshd

Minor changes to SSHd example
Merge pull request #8544 from SvenDowideit/link-to-latest-b2d-installers

Link directly to the 'latest' release alias
Merge pull request #8238 from vbatts/vbatts-daemon_timestamps

daemon logging: unifying output and timestamps
Merge pull request #8599 from irachex/commit_docs

Fix commit api document