URL hacking to easily transform production to local

See #1232
fix blank response for wp comment list --format-ids
adding functional tests
Merge pull request #1406 from wp-cli/fix-comment-list-format-ids

Fix blank response for wp comment list --format-ids
Force https when accessing WordPress.org

WordPress.org started redirecting to https anyway. Sometimes WordPress.org APIs return http though.
Merge pull request #1409 from wp-cli/force-https-wordpress

Force https when accessing WordPress.org