add a send_if_sunday rake task
add instructions for deploying to heroku
use clearer method for checking date
link to more specific subset of heroku addons
fix incomplete sentence
add line about manual testing on heroku
have rake task for heroku automatically send at beginning of week
remove remaining reference to sundays specifically
fix use of undefined method in rails < 4.0.2
create time wrapper class
Merge remote-tracking branch 'origin/master' into send-if-sunday

Conflicts:
	lib/tricle/aggregation.rb
fix method usage for rails 3
Merge pull request #72 from afeld/send-if-sunday

add Heroku (Scheduler) support