Various cleanups to Ubuntu installation instructions:

* Avoid editing /etc/apt/sources.list add nginx repo, instead create
  /etc/apt/sources.list.d/nginx.list

* Avoid editing /etc/nginx/nginx.conf, instead put server_name_hash_buckets
  setting into discourse.conf

* Proper-case Discourse when it is referring to the product name, so that all
  the lowercase references are to the user created during the installation
Address @Supermathie's concerns in PR1430
fix typos in EN translations
Attempt to fix spec under vagrant
BUGFIX: Top page wasn't display any topics
BUGFIX: missing localization for auto watching topics
FEATURE: added suppress_uncategorized_badge

site setting to remove the suppression of the uncategorized badge from topic lists
BUGFIX: dots in the wrong spot
Ember wants a ListTopController, not a TopController
update fixture
BUGFIX: cache did not support non strings

also reduced mocking in tests
copyedit on /top page orientation text
internationalize Discourse.Formatter.tinyDateYear
Merged new strings from *.en.yml and completed the Danish translation
Allow groups to be used as aliases for user mention

when configured by the admin a group can be found through the @mentions
feature in both the compose/reply and the private message user-selectors
and once selected the mention will be replaced by the list of users in
the group
Merge pull request #1796 from wulff/feature-wulff-update-danish-l10n

Merged new strings from *.en.yml and completed the Danish translation
FIX: vagrant up may fail when copying redis.yml. we don't need to copy it anymore.
BUGFIX: we should not store absolute urls for locally uploaded avatar templates

Highly recommended to run: `RAILS_ENV=production bundle exec rake avatars:regenerate` to fix the avatar templates stored in the database.
move alias levels into enums
Add spinner when authenticating with 3rd party. Also handle when popup window is closed without making a callback.