Optional xxHash support and native SHA2-256 from browser Web Crypto API or Node.js crypto

[mrauhu]

Hello @pi0.

I created the useHash() function that supported the xxHash32 algorithm from hash-wasm or native SHA-256 (with fallback).

Resolves #14, differences:

• for smaller base64 hashes (< 10 symbols) used xxHash32 (5.(3) unpadded bytes, 8 padded, max value — /////w==),
  instead of xxHash64 (10.(6) unpadded bytes, 12 padded, max value — //////////8=);
• fallback to SHA2-256 if the hash-wasm package is not installed:
  • Web Crypto API global crypto variable (browser and Node.js);
  • Web Crypto API from crypto module (Node.js);
  • createHash() from crypto module (Node.js);
  • sha256base64().

From my point of view, best solution it's to change the hashed string max length from 10 to 11 bytes and use the xxHash64 algorithm instead.

Added tests for #11 issue for xxHash32 and SHA-256 algorithms.

Example of usage

import { useHash } from 'ohash';

const hash = await useHash();

const key = await hash(obj);

Best wishes,
Sergey.