Support Puma web server

Created by: denji

• Puma/Unicorn init script for BSD @denvazh

sudo echo 'gitlab_enable="YES"' >> /etc/rc.conf
# gitlab_dir=/usr/home/services/git/gitlab
# gitlab_user=git
# gitlab_env=production

• Patches below has few improvements to the gitlab check and task_helper
• Support puma_worker_killer for killing worker at leakage Puma
• Rake scripts to verify whether init script was installed on FreeBSD and OSX (LaunchDaemon)

Gems Puma without Unicorn:

$ bundle install --without development test [mysql|postgres] unicorn \
 --path vendor/bundle --no-deployment

# Application server
group :unicorn do
  gem "unicorn", '~> 4.6.3'
  gem 'unicorn-worker-killer'
end
+
+group :puma do
+  gem 'puma'
+  gem 'puma_worker_killer'
+  #gem 'puma_auto_tune'
+end

Refs:

• https://gitlab.com/gitlab-org/gitlab-recipes/issues/26
• Puma/Sidekiq init-script
• Patches below has few improvements to the gitlab check and task_helper