Update Flask documentation (2.0.x)

Author: simon04

assets/javascripts/templates/pages/about_tmpl.coffee

@@ -308,7 +308,7 @@ credits = [
     'https://fishshell.com/docs/current/license.html'
   ], [
     'Flask',
-    '2007-2020 Pallets',
+    '2007-2021 Pallets',
     'BSD',
     'https://github.com/pallets/flask/blob/master/LICENSE.rst'
   ], [

lib/docs/scrapers/flask.rb

@@ -14,10 +14,15 @@ class Flask < UrlScraper
     options[:skip_patterns] = [/\Atutorial\//]
 
     options[:attribution] = <<-HTML
-      &copy; 2007&ndash;2020 Pallets<br>
+      &copy; 2007&ndash;2021 Pallets<br>
       Licensed under the BSD 3-clause License.
     HTML
 
+    version '2.0' do
+      self.release = '2.0.x'
+      self.base_url = "https://flask.palletsprojects.com/en/#{self.release}/"
+    end
+
     version '1.1' do
       self.release = '1.1.x'
       self.base_url = "https://flask.palletsprojects.com/en/#{self.release}/"