Revert "Small edit to the if statement simplification for blank? on the Object...

Revert "Small edit to the if statement simplification for blank? on the Object class. An Object doesn't need to be nil and empty to be blank? just one or the other."

Reason: the original code is correct, see

    !nil && !empty -> !(nil || empty) -> !blank

That said, this example has too many negations
for my linking. Think should be revised to be
more positive and straightforward to read.

This reverts commit a4b6e3d9.

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

@@ -4,7 +4,7 @@ class Object
   #
   # This simplifies:
   #
-  #   if !address.nil? || !address.empty?
+  #   if !address.nil? && !address.empty?
   #
   # ...to:
   #