revises comment for blank? method

activesupport/lib/active_support/core_ext/object/blank.rb

@@ -1,14 +1,14 @@
 class Object
   # An object is blank if it's false, empty, or a whitespace string.
-  # For example, "", "   ", +nil+, [], and {} are blank.
+  # For example, "", "   ", +nil+, [], and {} are all blank.
   #
   # This simplifies:
   #
-  #   if !address.nil? && !address.empty?
+  #   if address.nil? || address.empty?
   #
   # ...to:
   #
-  #   if !address.blank?
+  #   if address.blank?
   def blank?
     respond_to?(:empty?) ? empty? : !self
   end