convert app configuration to use ActiveRecord

note at this stage the app will not work because the models are still
configured to use MongoMapper
move yaml config files into the config directory

all of the configuration specific files should be there
migrate Users to ActiveRecord
migrate Competitions to ActiveRecord
migrate Teams to ActiveRecord
update controllers/views to use ActiveRecord syntax

for the most part everything is similar to MongoMapper, but there are a
few differences (Model.first and model._id)