Update gem source

Gemfile

-source 'https://rubygems.org'
-# source 'https://gems.ruby-china.org'
+#source 'https://rubygems.org'
+#source 'https://gems.ruby-china.org'
+source 'http://mirrors.tuna.tsinghua.edu.cn/rubygems'
 
 
 gem 'capistrano'
 gem 'capistrano'
 gem 'capistrano-rvm'
 gem 'capistrano-rvm'

Gemfile.lock

 GEM
 GEM
-  remote: https://rubygems.org/
+  remote: http://mirrors.tuna.tsinghua.edu.cn/rubygems/
   specs:
   specs:
     airbrussh (1.1.1)
     airbrussh (1.1.1)
       sshkit (>= 1.6.1, != 1.7.0)
       sshkit (>= 1.6.1, != 1.7.0)