Update D3.js documentation (5.1.0)

assets/javascripts/templates/pages/about_tmpl.coffee

@@ -207,7 +207,7 @@ credits = [
     'https://raw.githubusercontent.com/dlang/phobos/master/LICENSE_1_0.txt'
   ], [
     'D3.js',
-    '2010-2017 Michael Bostock',
+    '2010-2018 Michael Bostock',
     'BSD',
     'https://raw.githubusercontent.com/d3/d3/master/LICENSE'
   ], [

lib/docs/scrapers/d3.rb

@@ -12,10 +12,26 @@ module Docs
     options[:container] = '.markdown-body'
 
     options[:attribution] = <<-HTML
-      &copy; 2010&ndash;2017 Michael Bostock<br>
+      &copy; 2010&ndash;2018 Michael Bostock<br>
       Licensed under the BSD License.
     HTML
 
+    version '5' do
+      self.release = '5.1.0'
+      self.base_url = 'https://github.com/d3/'
+      self.root_path = 'd3/blob/master/API.md'
+
+      html_filters.push 'd3/clean_html', 'd3/entries_v4'
+
+      options[:only_patterns] = [/\Ad3[\-\w]+\z/, /\Ad3\/blob\/master\/changes\.md\z/i]
+      options[:skip_patterns] = [/3\.x-api-reference/]
+
+      options[:fix_urls] = ->(url) do
+        url.sub! %r{/blob/master/readme.md}i, ''
+        url
+      end
+    end
+
     version '4' do
       self.release = '4.12.2'
       self.base_url = 'https://github.com/d3/'