Merge pull request bitcoin#1564 from bitjson/patch-1

feat: add TypeScript BIP39 implementation

Author: Roasbeef

bip-0039.mediawiki

@@ -171,6 +171,9 @@ JavaScript:
 * https://github.com/dashhive/DashPhrase.js
 * https://github.com/hujiulong/web-bip39
 
+TypeScript:
+* https://github.com/bitauth/libauth
+
 Java:
 * https://github.com/bitcoinj/bitcoinj/blob/master/core/src/main/java/org/bitcoinj/crypto/MnemonicCode.java