require the Card.rb in an initializer to circumvent deserializing issue that heroku can't handle but localhost can
try another solution -- precompiling assets since heroku failed on precompile step
try to fix heroku again by turning off initialize on precompile
try again to fix heroku by moving the precompile initialize = false to required_classes.rb initializer
add the rails 12_factor gem that heroku needs to try and fix rails 4 asset issues