Changelog

`v2.1.1`

TypeScript typings fix: omit Data base class keys in create() and copy() signatures. Not a breaking change since attempt to override these keys would lead to runtime error already. Mainly affects autocomplete function of your editor, only showing the keys that can be updated.

Data instances are now sealed. Adding extra keys via create() or copy() will result in runtime error. If type system is properly utilized, this should not create any issues to existing code.
Fully rewritten instantiation and copy algorithms with backward compatibility. New implementation consumes less memory and uses faster approach in copying objects.
Fixed dynamic defaults being re-generated after copy()
copy() methods now both can omit the argument, creating a referential copy of the instance.
equals() now compares all keys (previously it was checking only the ones overriding defaults). The assumed optimizaiton in time didn't pay out and only caused unnecessary complication to copying mechanism and higher memory consumtion.

Dataclass is now licensed under ISC License
https://github.com/alexeyraspopov/dataclass/blob/master/LICENSE
Breaking: the utility class has been renamed from Record to Data
- "Record" now means a lot of other things in the ecosystem
Breaking: use .create() static method instead of new operator
- This fixes the issue with existing browser implementation of class properties
- The use of new operator now throws a runtime error
Breaking: TypeScript classes no longer need to be generic
Breaking: an attempt to mutate properties now throws runtime errors
Breaking: use named import instead of default import { Data } from "dataclass"
- This should fix possible CJS/ESM compatibility issues and allow future API extensions
Breaking: explicit toJSON() implementation has been removed, but the behavior is preserved
Breaking: library code is no longer transpiled to ES5
- Unless you support evergreen browsers, you still need to transpile TypeScript or class properties so the build step is inevitable. Thus, make sure dataclass is transpiled if necessary
Fixed equals() algorithm to ensure proper custom values comparison
Fixed equals() algorithm to avoid runtime errors for nullable properties
Added sideEffects: false to package.json