Change rake task 'verbose' parameter

The verbose option does not work anymore, so we have to explicitly pass
the '--verbose' option now.

Author: nadjaheitmann

Rakefile

@@ -17,7 +17,7 @@ Rake::TestTask.new(:test) do |t|
   t.libs << 'lib'
   t.libs << 'test'
   t.test_files = FileList['test/**/*_test.rb']
-  t.verbose = true
+  t.options = '--verbose'
   t.ruby_opts = ["-W1"]
 end