Decouple Google ML Kit from codebase

[czlucius]

Code, ScanningWrapper, and many other classes have been coupled to Google's ML Kit in one way or another (using Barcode, or ML Kit's type constants).

One suggestion is to use a Translator to "translate" the data from an abstract source(zxing, Google/Huawei ML Kit, etc.) into a general format in Code (e.g. Code's constructor accepting Barcodes will be replaced by a Translator which helps to convert them into a Code.) to decouple Google ML Kit from the codebase.