Refactor: Topic#invite_by_email

Extract Topic#email_already_existas_for? and Topic#grant_permission_to_user
Fix failing spec due to missing variable in extracted method
Add script to install mandatory config files from their .sample version.
Standardize on 'worker' for sidekiq Procfile entry (expected by buildpack).
Copy default production.rb file.
Allow to set SMTP settings via environment variable.
refactors Discourse.Computed to bind context to self
Refactor: Topic#invite_by_email

Extract Topic#email_already_existas_for? and Topic#grant_permission_to_user
Fix failing spec due to missing variable in extracted method
Merge branch 'refactor-topic-invite-by-email' of github.com:cored/discourse into refactor-topic-invite-by-email
add a rake task to pull hotlinked images
fix initialization issues with unicorn
amend unicorn script to demonize sidekiq
create a sidekiq demon that unicorn consumes
correct bug in exec_sql with empty params
rails 4 upgrade
rack lock is trouble, nuke it out of orbit
more aggressive suicide for forked sidekiq
work around startup issue
Merge pull request #1505 from crohr/debian-packaging-with-pkgr

Debian packaging with pkgr
Merge pull request #1513 from velesin/computed_self_refactoring

refactors Discourse.Computed to bind context to self
css.scss makes rails 4 sad
Changed the client Spanish translation

As per my previous pull request.
(experimental) added framework for filtering all sorts of internals in discourse and consuming by plugins
Merge pull request #1515 from davguij/master

Changed the client Spanish translation
update images:pull_hotlinked rake task to add support for the markdown reference link style