update release checklist and .gitignore

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)
Added Release Notes

Release notes for v.1.1 have been added to the docs index.md page. Made some revisions to
other content to make it shorter.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Fixed numerous inconsistencies in command help text

* Replaced docker with Docker.
* Consistently used STDIN, STDOUT, STDERR.
* Consistently used TTY.
* Fixed some grammar and spelling issues.
* Fixed references to the index.

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: jamtur01)

Docker-DCO-1.1-Signed-off-by: James Turnbull <james@lovedthanlost.net> (github: SvenDowideit)
Update cli.md and man pages to match current cli

Docker-DCO-1.1-Signed-off-by: SvenDowideit <SvenDowideit@home.org.au> (github: SvenDowideit)
Merge pull request #6790 from SvenDowideit/pr_out_update_cli_md

update cli.md
I'm going to wish I didn't do this

Docker-DCO-1.1-Signed-off-by: SvenDowideit <SvenDowideit@home.org.au> (github: SvenDowideit)
Merge pull request #6807 from SvenDowideit/convert-more-docker.io-to-docker.com

some docker.io -. docker.com conversions
Merge pull request #6819 from vieux/update_release_checklist_and_gitcommit

update release checklist and .gitignore
Corrected version number to 3 digits.

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Merge pull request #6824 from fredlf/1-1_release_notes

Added Release Notes
Bump version to v1.1.0

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)