Fix WP import so topics have the right keys

The Juvia JS looks up topics using a key that it gets from `location.pathname`. For `mydomain.com/my/post`, this is `/my/post`. When the WP import script runs, it creates the keys as `mydomain.com/my/post`, meaning that the topics are not correctly fetched by the JS on each page.
Update word_press.rb
add rel="nofollow" to all links in comments
remove protocol from gravatar url

if parent uses https, requesting anything over http will trigger a
browser warning
Merge pull request #42 from tribut/gravatar-https

remove protocol from gravatar url
Added comment_order description to the help page, as @alexander-yakushev pointed out on issue #30 that I hadn't added this with my original pull request.
Merge branch 'master' of https://github.com/phusion/juvia
Merge pull request #41 from tribut/rel-nofollow

add rel="nofollow" to all links in comments
Manually merged change to add auto-linking (see pull request #37) as this can no longer be auto-merged
Merge pull request #33 from ianrenton/temp-pullreq-multisite

Fix WP import so topics have the right keys