Create Exception classes for Product and Price services

This PR creates concrete exception classes for SoapProductService and SoapPriceService and wraps the SOAP calls in try/catch blocks. We now catch and rethrow UnsupportedCurrencyExceptions for the Product and Price services, and for the Product service, we catch generic exceptions and rethrow them as either a ProductServiceCreateException or ProductServiceUpdateException. This should hopefully allow us to be more intelligent about our exception handling when syncing a product with CBS, because we currently only listen for generic Exceptions and can't easily react to issues that arise from one type of call or the other.

Please review: @weizhong-wang @lloyd-carter @KJOYNER

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merged

mentioned in commit d8802a13