Merge remote-tracking branch 'upstream/master' into update-locale-vietnamese

* upstream/master: (185 commits)
  SECURITY: Upgrade rails.
  FIX: new user summary page was broken
  Version bump to v1.5.0.beta9
  Remove addressable from Discourse.
  UX: change glyph when inviting existing user to a topic
  FIX: Allow for large free disk space
  Revert "FIX: disk_space should be a BigDecimal to handle large disk (closes #3923)"
  UX: improve styling of messages and mobile view of messages
  FIX: correct counts on user summary
  FIX: link to filtered down list of badges from summary FEATURE: pick featured badges in summary page
  FIX: do not allow new email to be duplicate FIX: return proper error message when email already exists
  retain unactivated accounts a bit longer default
  FEATURE: blocked users can send and reply to private messages from staff
  Remove Arel patch that has been merged upstream.
  correct path
  little typo
  FIX: Missing tag in CSS.
  PERF: remove 10-20ms of work from every page view
  FIX: remove green background for wiki (this can be re-added via a customization if needed)
  Hotfix for unsubscribe via email
  ...

# Conflicts:
#	.tx/config

.tx/config

@@ -1,6 +1,6 @@
 [main]
 host = https://www.transifex.com
-lang_map = es_ES: es, fr_FR: fr, ko_KR: ko, pt_PT: pt, vi_VN: vi
+lang_map = es_ES: es, fr_FR: fr, ko_KR: ko, pt_PT: pt, sk_SK: sk, vi_VN: vi
 
 [discourse-org.clientenyml]
 file_filter = config/locales/client.<lang>.yml