prospect-offer-payment-crud - implement crud, implement add & edit forms

• v0.1: implement crud, implement add & edit forms, add edit-payment & delete-payment buttons to table row, add-payment button in prospect details, discard import.html refactor to list.html, add auctionCode to payment model, add migration, add validationRegex via input pattern, style changes
• v0.2: fixes...
• v0.3: refactor add & edit structure (to only BankAccNumber & Amount), implement paymentCode & prospectCode generate methods, add unlinkOffer method, refactor create & update methods in service (conditional auctionCode & offerId)