fix tests for ruby 2.1 and add 2.1 to ci test matrix

.travis.yml

@@ -2,6 +2,7 @@ language: ruby
 rvm:
  - 1.9.3
  - 2.0.0
+ - 2.1
 
 before_install:
   - "mysql -e 'create database tracks_test;'"

test/fixtures/recurring_todos.yml

@@ -20,7 +20,7 @@ def two_weeks_hence
 end
 
 def way_back
-  Time.zone.local(2008,1,1)
+  Time.zone.local(2008,1,1).to_s(:db)
 end
 
 %>