FIX: add vary encoding to gzip responses

this ensures CDNs work correctly see: http://blog.maxcdn.com/accept-encoding-its-vary-important/
FEATURE: search by ip address on admin user list page
add post_number to PostWordpressSerializer
Merge pull request #2903 from santouras/fix/adjust-wp-serializer

Add post_number to PostWordpressSerializer
Update Translations
Merge pull request #2904 from techAPJ/patch-2

Update Translations
Version bump to v1.1.0.beta7
fix size of quote avatars in email
FIX: When uncategorized badge is not suppressed, the header formatting
was a bit messed up
Merge pull request #2902 from techAPJ/patch-1

FEATURE: search by ip address on admin user list page
FIX: Broken "read more" link on categories view for mobile pinned topics
FEATURE: Include category / subcategory name in document title when
viewing a topic.
FIX: disposable invite was giving email validation error
Merge pull request #2905 from techAPJ/patch-3

FIX: disposable invite was giving email validation error
make sure categories don't wrap in email digests
Moderators can search users by ip address
Merge pull request #2906 from techAPJ/patch-3

Moderators can search users by ip address
include all groups in user csv export
Merge pull request #2907 from techAPJ/patch-1

include all groups in user csv export
Show dismiss posts/topics buttons on category filtered lists