Merge branch 'release/0.6.67' into develop
Fix for timer running slowly in a background tab by comparing Date objects.
Merge pull request #90 from gunn/develop

Fix for #89 - timer running slowly

Seems good to me, it's going online with version 0.6.68.

Thanks for your help @gunn
Use Unicorn instead of Thin

See https://blog.heroku.com/archives/2013/2/27/unicorn_rails
bump version number to 0.6.68
Merge branch 'release/0.6.68'