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
YoutubeOnebox: FIX HTTP-specific URLs

by replacing with protocol-agnostic URLs.
This fixes the mixed-content warning for secure instances of discourse, at least for Youtube
Merge pull request #1514 from cfstras/youtube-https

YoutubeOnebox: FIX HTTP-specific URLs
Improve the wording of the spam_post_blocked notification
rate limits for topics and posts on first day
max_topics_in_first_day and max_replies_in_first_day
this setting needs to be pushed up to 15 so we will be able to nuke new spammer accounts

it is set to max_topics_in_first_day + max_replies_in_first_day
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