Fixed rspec not work with Rails 2.2.1

Author: lgn21st

Gemfile

@@ -95,4 +95,8 @@ group :test do
   gem 'launchy'
   gem 'selenium-webdriver'
   gem 'poltergeist'
+
+  # rspec-rails rely on test-unit if rails version less then 4.1.0
+  # but test-unit has been removed from ruby core since 2.2.0
+  gem 'test-unit'
 end

Gemfile.lock

@@ -270,6 +270,7 @@ GEM
       cliver (~> 0.3.1)
       multi_json (~> 1.0)
       websocket-driver (>= 0.2.0)
+    power_assert (0.2.2)
     pry (0.9.12.6)
       coderay (~> 1.0)
       method_source (~> 0.8)
@@ -392,6 +393,8 @@ GEM
       sprockets (>= 2.8, < 4.0)
     structured_warnings (0.1.4)
     temple (0.6.7)
+    test-unit (3.0.8)
+      power_assert
     thor (0.19.1)
     thread_safe (0.1.3)
       atomic
@@ -502,6 +505,7 @@ DEPENDENCIES
   simple_captcha2
   simple_form (~> 3.1.0)
   slim-rails
+  test-unit
   timecop
   twilio-ruby (~> 3.11)
   uglifier