Remove unneeded requires

We should not require all the core extensions inside the frameworks.
The logger is already defined in the Action View framework.

actionpack/lib/action_view/digestor.rb

@@ -1,6 +1,3 @@
-require 'active_support/core_ext'
-require 'logger'
-
 module ActionView
   class Digestor
     EXPLICIT_DEPENDENCY = /# Template Dependency: ([^ ]+)/
@@ -61,7 +58,7 @@ module ActionView
       def logical_name
         name.gsub(%r|/_|, "/")
       end
-      
+
       def directory
         name.split("/").first
       end
@@ -74,7 +71,6 @@ module ActionView
         @source ||= finder.find(logical_name, [], partial?, formats: [ format ]).source
       end
 
-
       def dependency_digest
         dependencies.collect do |template_name|
           Digestor.digest(template_name, format, finder, partial: true)
@@ -92,7 +88,7 @@ module ActionView
 
           # render("headline") => render("message/headline")
           collect { |name| name.include?("/") ? name : "#{directory}/#{name}" }.
-          
+
           # replace quotes from string renders
           collect { |name| name.gsub(/["']/, "") }
       end
@@ -101,4 +97,4 @@ module ActionView
         source.scan(EXPLICIT_DEPENDENCY).flatten.uniq
       end
   end
-end
+end