remove commented code and make assert_contain use a true assertion

lib/webrat/core/matchers/have_content.rb

@@ -55,14 +55,14 @@ module Webrat
     # the supplied string or regexp
     def assert_contain(content)
       hc = HasContent.new(content)
-      raise Test::Unit::AssertionFailedError.new(hc.failure_message) unless hc.matches?(response_body)
+      assert hc.matches?(response_body), hc.failure_message
     end
     
     # Asserts that the body of the response
     # does not contain the supplied string or regepx
     def assert_not_contain(content)
       hc = HasContent.new(content)
-      raise Test::Unit::AssertionFailedError.new(hc.negative_failure_message) if hc.matches?(response_body)
+      assert !hc.matches?(response_body), hc.negative_failure_message
     end
     
   end

spec/public/matchers_spec.rb

@@ -254,6 +254,7 @@ describe Webrat::Matchers do
     end
     
     describe "asserts for contains," do
+        include Test::Unit::Assertions
       before(:each) do
         should_receive(:response_body).and_return @body
         require 'test/unit'