Improve error reporting of invalid response

[markus-mohemian]

Changes

• Updated NFCPassportReaderError.InvalidResponse to provide more information regarding the datagroup and the read tag
• Added a new error case Unknown(Error) to handle errors not directly handled by the SDK
• Added tests to cover the improved output
• dataGroupType is now a computed property. This change makes it readonly and also available when an error needs to be thrown in parse method
• Fixed an issue in PassportReader by removing nfcContinuation calls here as this is called in invalidateSession

Background

We experienced problems in capturing which datagroups were responsible for InvalidResponse errors. To deal with this the datagroup together with expected and actual tag information is returned back.

⚠️ Breaking changes

• Errors that occur in PassportReader.readDataGroup(tagReader: TagReader, dgId: DataGroupId) will now be rethrown instead of being ignored. This is necessary in order to return the error back to the SDK consumer. Personally I think it's better to fail than to return successfully w/o any data, but there might be cases were this is not a good idea.

Resolves #54

[markus-mohemian]

Hi @AndyQ, any feedback on this one?

[AndyQ]

I'll take a look - thanks!

[AndyQ]

Merged - thanks