HARDENED_OFFSET is not a static property of HDKey

[mahnunchik]

According to the documentation HARDENED_OFFSET should be a static property of HDKey class:

scure-bip32/README.md

Line 56 in 2274f2f

public static HARDENED_OFFSET: number;

But HARDENED_OFFSET is exported as named export

scure-bip32/index.ts

Line 26 in 2274f2f

export const HARDENED_OFFSET: number = 0x80000000;