Add poll plugin.
Removing more stuff from the sanitizer whitelist
Remove audio and video tags as well
Allow users to toggle interface language in their preferences
Add a site setting to allow users to toggle I18n.locale

It is false by default.
Restore 'article' to whitelist
simplify TopicPostersSummary
BUGFIX: backup/restore rake tasks weren't working
BUGFIX: actually use db_conf everywhere
BUGFIX: missed a spot in the backup rake task
fix typo
Adds specs for PostsController#by_number.
BUGFIX: do not push read-only signal to ALL sites
Merge pull request #1978 from velesin/posts_controller__by_number_tests

Adds specs for PostsController#by_number.
Merge pull request #1922 from joallard/language-toggle

Allow users to toggle interface language in their preferences
Merge pull request #1975 from orend/simplify_topic_posters_summary

simplify TopicPostersSummary
Merge pull request #1948 from riking/patch-3

Removing more stuff from the sanitizer whitelist
Merge pull request #1903 from vikhyat/poll-plugin

Add poll plugin
FIX: Allow closing the category dropdown when clicking on the same
category
Allow jump to top on post 2 or 3.