move transaction service and models to core

src/app/core/models/transaction-query.ts

src/app/core/models/transaction.ts

src/app/core/public-api.ts

src/app/core/resources/transaction-resource.service.ts

src/app/core/services/transaction.service.spec.ts

src/app/core/services/transaction.service.ts

...mponents/last-transactions/last-transactions.component.ts

...d/components/new-transaction/new-transaction.component.ts

src/app/dashboard/dashboard.module.ts

src/app/dashboard/resources/account-resource.service.ts

src/app/dashboard/services/accounts.service.ts