Add rake task to run new unit tests

tasks/test.rake

@@ -2,8 +2,13 @@ require 'rake/testtask'
 require 'rspec/core/rake_task'
 
 namespace :test do
-  Rake::TestTask.new do |t|
+  RSpec::Core::RakeTask.new do |t|
     t.name = "unit"
+    t.pattern = "test/unit/**/*_test.rb"
+  end
+
+  Rake::TestTask.new do |t|
+    t.name = "unit_old"
     t.libs << "test/unit_legacy"
     t.pattern = "test/unit_legacy/**/*_test.rb"
   end