Local base58 alphabet check for better errors (#622)

* Local base58 alphabet check for better errors

* Rewrite yarn.lock

* Align error return values

* Split base58{Encode, Decode}

* base58Encode input types

* Function names, some docs

packages/util-crypto/src/base58/encode.ts

@@ -0,0 +1,18 @@
+// Copyright 2017-2020 @polkadot/util-crypto authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import bs58 from 'bs58';
+import { u8aToBuffer, u8aToU8a } from '@polkadot/util';
+
+/**
+ * @name base58Encode
+ * @summary Creates a base58 value.
+ * @description
+ * From the provided input, create the base58 and return the result as a string.
+ */
+export default function base58Encode (value: Uint8Array | string | Buffer | number[]): string {
+  return bs58.encode(
+    u8aToBuffer(u8aToU8a(value))
+  );
+}