Import public GPG key after adding the openSUSE repository

Docker-DCO-1.1-Signed-off-by: Christian Berendt <berendt@b1-systems.de> (github: berendt)
Remove superfluous reptition from usingdocker.md

Clarify wording about default docker ps options

Fix typo in dockerlinks.md

Docker-DCO-1.1-Signed-off-by: Paul Weaver <pauweave@cisco.com> (github: ch3pjw)
Update nodejs_web_app.md

Docker-DCO-1.1-Signed-off-by: Hyeongkyu Lee <hyeongkyu.lee@navercorp.com> (github: leeplay)
Merge pull request #6712 from SvenDowideit/pr_out_remove_superfluous_reptition_from_usingdocker_md

Remove superfluous reptition from usingdocker.md
Merge pull request #6676 from berendt/opensuse_import_public_gpg_key

Import public GPG key after adding the openSUSE repository
Merge pull request #6716 from leeplay/master

Update nodejs_web_app.md