Update Node.js documentation (7.4.0, 6.9.4, 4.7.2)

lib/docs/scrapers/node.rb

@@ -23,17 +23,17 @@ module Docs
     HTML
 
     version do
-      self.release = '7.3.0'
+      self.release = '7.4.0'
       self.base_url = 'https://nodejs.org/dist/latest-v7.x/docs/api/'
     end
 
     version '6 LTS' do
-      self.release = '6.9.2'
+      self.release = '6.9.4'
       self.base_url = 'https://nodejs.org/dist/latest-v6.x/docs/api/'
     end
 
     version '4 LTS' do
-      self.release = '4.7.0'
+      self.release = '4.7.2'
       self.base_url = 'https://nodejs.org/dist/latest-v4.x/docs/api/'
     end
   end