Merge branch 'zj-api-v4' into 'master'

Use APIv4 for verification

See merge request !66

verify_templates.rb

 require 'net/http'
 require 'json'
-uri = URI.parse 'https://gitlab.com/api/v3/ci/lint'
+uri = URI.parse 'https://gitlab.com/api/v4/ci/lint'
 Dir.glob("#{File.dirname(__FILE__)}/**/*.yml").each do |file|
   response = Net::HTTP.post_form(uri, content: File.read(file))