add activerecord to gemfile

Gemfile

-source "http://rubygems.org"
-gem "shoulda"
-gem "mocha"
-gem "rake"
-# gem "ruby-debug", :platform => :ruby_18
-# gem "ruby-debug19", :platform => :ruby_19
-gem "jruby-openssl", :platform => :jruby
-gem "aws-s3", :require => "aws/s3"
-gem "sqlite3", "~>1.3.4"
+source :rubygems
+
+gem "activerecord", :require => "active_record"
 gem "appraisal"
 gem "appraisal"
-gem "fog"
+gem "aws-s3", :require => "aws/s3"
 gem "bundler"
 gem "bundler"
 gem "cocaine"
 gem "cocaine"
+gem "fog"
+gem "jruby-openssl", :platform => :jruby
 gem "mime-types"
 gem "mime-types"
+gem "mocha"
+gem "rake"
 gem "rdoc", :require => false
 gem "rdoc", :require => false
+gem "shoulda"
+gem "sqlite3", "~>1.3.4"
+
+# gem "ruby-debug", :platform => :ruby_18
+# gem "ruby-debug19", :platform => :ruby_19

Gemfile.lock

 GEM
 GEM
   remote: http://rubygems.org/
   remote: http://rubygems.org/
   specs:
   specs:
+    activerecord (2.3.12)
+      activesupport (= 2.3.12)
+    activesupport (2.3.12)
     appraisal (0.3.5)
     appraisal (0.3.5)
       aruba (~> 0.3.6)
       aruba (~> 0.3.6)
       bundler
       bundler
@@ -74,6 +77,7 @@ PLATFORMS
   ruby
   ruby
 
 
 DEPENDENCIES
 DEPENDENCIES
+  activerecord
   appraisal
   appraisal
   aws-s3
   aws-s3
   bundler
   bundler