Fix installation docs to use the new boot2docker command: ip

Docker-DCO-1.1-Signed-off-by: Lajos Papp <lajos.papp@sequenceiq.com> (github: lalyos)
full url to GCE image

Docker-DCO-1.1-Signed-off-by: Adam Singer <financeCoding@gmail.com> (github: financeCoding)
Update windows.md

Update Program Files path description, the default install folder is "Boot2Docker", rather than "Docker"
Fix typo in networking.md

Minor typo fix
Merge pull request #6564 from financeCoding/docs-installation-google-fix

full url to GCE image
Minor typo/format fixes

This fixes a code block typo so it renders as a code block.  Additionally synchronizes the variable prefix examples from 'DB' and 'DB1_' to 'DB_' and 'DB1_'
Merge pull request #6566 from jokajak/patch-1

Fix typo in networking.md
Merge pull request #6540 from lalyos/docs-installation-mac-windows

Fix installation docs to use the new boot2docker command: ip
Merge pull request #6568 from jokajak/patch-2

Minor typo/format fixes for dockerlinks.md
Merge pull request #6565 from shaunol/patch-1

Update windows.md
Implement tail for docker logs

Fixes #4330
Docker-DCO-1.1-Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com> (github: LK4D4)