Fix group matching SQL query

The check there is intended for the :members_mods_and_admins level, which is not automatically checked for normal users. Instead, the :everyone level is the one used, which would always fulfill the "alias_level in :levels" check.

This changes the :everyone level to :members_mods_and_admins, which was originally intended.
Change to case-insensitive matching in group @name matching
Simplify usage of unbound i18n helper
fixing some gutter link spacing that was bothering me
BUGFIXES: improved performance of import an export

we no longer generate the entire dump in memory, instead we generate one table at a time
added some basic progress
BUGFIX: avoid trasactions in test
Merge pull request #1880 from awesomerobot/master

fixing some gutter link spacing that was bothering me
BUGFIX: clicking on links to the same domain was broken
remplacer conversation par discussion (French locale)
BUGFIX: link to attachments when using S3
Merge pull request #1881 from frabrunelle/master

remplacer conversation par discussion (French locale)
making @mention background darker in blockquotes
REMOVE: Get rid of the `hotness` control for good.
REMOVE: `discourse_poll` has not worked for over a year now. Let's
remove it.
Show discourse logo as system user avatar
FIX: use actions in user_stream_view.js
Merge pull request #1882 from awesomerobot/master

making @mention background darker in blockquotes
Work in progress: Swap out onebox code for onebox gem
Appropriate Onebox style
Add DiscourseLocalOnebox