Core Twitter embed:
- Fixed twttr undefined error.
- Made sure embeds still work when another Twitter widget is included in page (e.g., in a pocket).
- Embed cards will now immediately display when posted, instead of on page refresh.
- Embed cards will transition in.
- Refactored code.
Merge branch 'stage' of github.com:vanilla/vanilla into feature/twitter-embed-fix
Fixes message popin excerpt filtering
Validate DeliveryType before setting
Plugins have been using an invalid DeliveryType forever.
Filters inbox popin with htmlspecialchars instead of PlainText
ProfileExtender: Allow options for text box.
Adds filtering to BodyBox format
Merge pull request #2066 from vanilla/feature/profileextender-textbox-options

ProfileExtender: Allow options for text box.
Merge pull request #2054 from vanilla/hotfix/security-aug

Filtering improvements
Conflicts:
	applications/vanilla/controllers/class.postcontroller.php
Merge branch 'feature/twitter-embed-fix' into stage

Conflicts:
	index.php
Notifications:  Add event to InformNotifications.
Merge pull request #2073 from vanilla/hotfix/inform-notifications

Notifications:  Add event to InformNotifications.
Merge branch 'master' into stage
Add Emoji->hasEditorList().
Merge pull request #2078 from vanilla/hotfix/emoji-editor-list

Add Emoji->hasEditorList().
Merge branch 'master' into stage
Fix bad merge.
Fire an event so that plugins can add buttons to conversations.