Add local config files to .gitignore
Remove generated controller specs
Finish Bill validation specs
Update BillSplit factory to reflect current model
::create_settle! returns the bill on success
remove superfluous associations on factory
Add settlement specs
Make currency factory more realistic
Easier to test rate
Add currency conversion specs
Add debtor assocation
Add specs for #display_name
Add spec for #user_ids_with_outstanding_balance
Add specs for #users_with_outstanding_balances
Add specs for #balance_with
Add specs for #splits_with