Remove Deprecated Code

When running code in a test suite, it would throw the following warning
messages:

    Deprecation Warnings:

    `failure_message_for_should_not` is deprecated. Use
    `failure_message_when_negated` instead. Called from
    lib/testing/rspec.rb:98:in `block in <top (required)>'.

    `failure_message_for_should` is deprecated. Use
    `failure_message` instead. Called from
    lib/testing/rspec.rb:90:in `block in <top (required)>'.

    If you need more of the backtrace for any of these deprecations to
    identify where to make the necessary changes, you can configure
    `config.raise_errors_for_deprecations!`, and it will turn the
    deprecation warnings into errors, giving you the full backtrace.

    2 deprecation warnings total

This change adopts the newer, generic DSL for writing RSpec matchers.

Author: kmwhite

lib/testing/rspec.rb

@@ -87,15 +87,15 @@ def validate_enum(enum_class, item)
       end
     end
 
-    failure_message_for_should do
+    failure_message do
       message = "should act as enumerated"
       if @items
         message << " and have members #{@items.inspect}"
       end
       message
     end
 
-    failure_message_for_should_not do
+    failure_message_when_negated do
       message = "should not act as enumerated"
       if @items
         message << " with members #{@items.inspect}"
@@ -131,11 +131,11 @@ def validate_enum(enum_class, item)
       model_class.has_enumerated?(attribute)
     end
 
-    failure_message_for_should do
+    failure_message do
       "expected #{attribute} to be an enumerated attribute"
     end
 
-    failure_message_for_should_not do
+    failure_message_when_negated do
       "expected #{attribute} to not be an enumerated attribute"
     end
 
@@ -166,11 +166,11 @@ def validate_enum(enum_class, item)
       end
     end
 
-    failure_message_for_should do
+    failure_message do
       "expected #{attribute} to match the enum"
     end
 
-    failure_message_for_should_not do
+    failure_message_when_negated do
       "expected #{attribute} to not match the enum"
     end
 
@@ -179,4 +179,4 @@ def validate_enum(enum_class, item)
     end
   end
 
-end
+end