Update client.it.yml to have category section

As outlined in this question:
http://meta.discourse.org/t/all-categories-on-non-english-sites/11417
Merge pull request #1735 from piac/patch-2

Update client.it.yml to have category section
Fix topics_year, topics_month, topics_week for uncategorized category
add more info to rss feeds
Merge pull request #1738 from alxndr/rss-tweaks

add more info to rss feeds