PMErrorType's cases are not visible from Swift

[tomaskraina]

Because enum PMErrorType is defined in a very oldschool way, it's not being correctly exposed to Swift and can't be used in a switch statement.

The correct way to define PMErrorType would be to use NS_ENUM macro like this:

typedef NS_ENUM(NSInteger, PMErrorType)
{
    UNKNOWN          = 0, /*Initial value*/
    WRONG_PARMETERS  = 1, /*You have supplied wrong parameters. You use message for details.*/
    HTTP_CONNECTION  = 2, /*There was an error while connecting to the PayMill Service.*/
    API              = 3, /*The PAYMILL API returned an unexpected result.*/
    SAFESTORE        = 4, /*The PAYMILL safe store returned an error. Check the PMSafeStoreErrorCodeKey in the user info dictionary for the specific error. */
    BRIDGE           = 5, /*The PAYMILL JS-Bridge returned an a payment method related error code. Check the PMBridgeErrorCodeKey in the user info dictionary for the specific error. */
    NOT_INIT         = 6, /*You did not initialize the SDK.*/
    INTERNAL         = 7, /*This should never happen. If you encounter it, please send email support@paymill.com .*/
};

More info on NS_ENUM macro and Swift/ObjC interoperability: https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/InteractingWithCAPIs.html