TwistyPuzzleLib

Very important bugfix for an issue which probably has been the reason for many mysterious behaviours in the past: the JsonReader class cannot be a singleton! Convert it into a normal 'instanced' class.
With it being a singleton there's a major issue: when we create a new TwistyObject from a JSON file (by, for example, going to PurchaseActivity) and then we come back to the old object (by, for example, going back to the main RubikActivity) - then the JsonReader inside the old object has read the new JSON file and thus many of the 'abstract' methods in the old TwistyObject (for example getShortName()) all of the sudden start returning new values!

Changes to the initialization - initialize the 'bought objects'

Make it possible to create Diamond and Icosahedron-shaped objects to be read from json.

More support for pillowing; pillow Morphix and Jing by default.

IAP, part 3: non-free objects appear in the popup with a lock icon.

IAP, part 1: Introduce the concept of a 'free' and 'not free' object to

- ObjectType
- DownloadedObject
- RubikObject
- jsons

Make ObjectSignature ready for any size bandaged cube.

main: license.

Do not crash when something's wrong with the JSON file - handle this gracefully, do not change the object then, and report this to Firebase.

Bugfix