Merge branch 'gitlab-redis' into 'master'

Put Redis loading code in one place

Before this change you could not run the gitlab_net specs in isolation.

See merge request !64

lib/gitlab_config.rb

-$:.unshift(File.expand_path(File.join(File.dirname(__FILE__), 'vendor/redis/lib')))
 require 'yaml'
 
 class GitlabConfig

lib/gitlab_net.rb

 require 'net/http'
 require 'openssl'
 require 'json'
-require 'redis'
 
 require_relative 'gitlab_config'
 require_relative 'gitlab_logger'
 require_relative 'gitlab_access'
+require_relative 'gitlab_redis'
 require_relative 'httpunix'
 
 class GitlabNet

lib/gitlab_redis.rb

+$:.unshift(File.expand_path(File.join(File.dirname(__FILE__), 'vendor/redis/lib')))
+require 'redis'