Added `openssl_verify_mode` parameter for action_mailer.

- parameter in `environments/production.rb`
- documentation & default value (nil) in `discourse_defaults.conf`
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One more line for more space in new version email
FEATURE: backend for inviting a user to a group
Backend support for group invites
FEATURE: admins can invite users to groups via the web UI
Log the actual promise object instead of a useless name

 - console.log has support for objects including introspection, use this
 - instead of logging useless names
Merge pull request #2328 from ligthyear/better-debugging-of-promises-in-dev

Log the actual promise object instead of a useless name
suppress reply-to-tab borders
ES6: Some more controllers
Merge pull request #2304 from techAPJ/speech-bubble-update

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Revert "Merge pull request #2304 from techAPJ/speech-bubble-update"

This reverts commit 6590ebbcbee712d0759cff8c9dd8c1c12a00619b, reversing
changes made to 3855ead62ef1caabfeba970c999696cee20036c4.
Merge pull request #2327 from fantasticfears/patch-3

One more line for more space in new version email
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User lowercase names for seeded categories. Change colors of meta category badge for new sites.
Make oneboxes in emails look slightly less awful
Merge pull request #2329 from techAPJ/speech-bubble-updates

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First attempt: Move username on top of embedded posts
Move in reply to slightly in embedded posts
FIX: Some avatars were too big in embedded CSS