Move Template class docs to the correct namespace [ci-skip]

Documentation of a class should be defined above the class definition,
not on the parent namespace.
This fixes the documentation of ActionView::Template::Renderable showing
up in ActionView::Template.
Most of the others are marked with `:nodoc:` anyway, so it shouldn't affect
their documentation.

actionview/lib/action_view/template/handlers.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 module ActionView # :nodoc:
-  # = Action View Template Handlers
   class Template # :nodoc:
+    # = Action View Template Handlers
     module Handlers # :nodoc:
       autoload :Raw, "action_view/template/handlers/raw"
       autoload :ERB, "action_view/template/handlers/erb"

actionview/lib/action_view/template/html.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 module ActionView # :nodoc:
-  # = Action View HTML Template
   class Template # :nodoc:
+    # = Action View HTML Template
     class HTML # :nodoc:
       attr_reader :type
 

actionview/lib/action_view/template/raw_file.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 module ActionView # :nodoc:
-  # = Action View RawFile Template
   class Template # :nodoc:
+    # = Action View RawFile Template
     class RawFile # :nodoc:
       attr_accessor :type, :format
 

actionview/lib/action_view/template/renderable.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 module ActionView
-  # = Action View Renderable Template for objects that respond to #render_in
   class Template
+    # = Action View Renderable Template for objects that respond to #render_in
     class Renderable # :nodoc:
       def initialize(renderable)
         @renderable = renderable

actionview/lib/action_view/template/text.rb

@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 module ActionView # :nodoc:
-  # = Action View Text Template
   class Template # :nodoc:
+    # = Action View Text Template
     class Text # :nodoc:
       attr_accessor :type