Add RTL support to Discourse CSS pre-processing using the RTLit gem and configurable via discourse.conf
ensure rtlit gem in Gemfile is not required by default
ensure RTLit gem is included and CSS is RTLed if css_rtl is enabled in discourse config
Have reciever handle multiple To addresses
Use same reply-to format in all email fixtures
Add error reply for new error
Implement SSO overriding avatars.

Implemented by having Discourse download the image from the provided URL
and treating it as a custom upload.

Adds two more parameters to the SSO site’s response:

* `avatar_url` specifies the URL of the overriding avatar.
* `avatar_force_update` Discourse does not re-download avatars that
has already been download from the same URL. Setting this to true forces
Discourse to re-download the avatar in `avatar_url`

Note that both parameters are ignored if `sso_overrides_avatar` is set
to false.
Fix min_trust_level for wordpress

min_trust_level in the wordpress method was being set to 1 always, the order of the ternary operator was reversed.
Add link to Logster in "Logs" tab of admin panel
Update Translations
remove admin link on user drop down
Merge pull request #2681 from techAPJ/update-translations

Update Translations
UX: Add drop down for top lists, big refactor of repeated code.
FIX: Don't skip TOS check when using 3rd party auth
FIX: Firefox floating CSS, added calendar glyph to pop up
Version bump to v0.9.9.18
only hijack search on topic page
Merge pull request #2676 from riking/logster-link

Add link to Logster in "Logs" tab of admin panel
Merge pull request #2670 from Wilhansen/sso_override_avatar

Implement SSO overriding avatars.
Merge pull request #2633 from zohararad/master

Add RTL support to Discourse CSS Theme