Adding bip39 so I can use it to move around private keys.

git-svn-id: https://www.unprompted.com/svn/projects/tildefriends/trunk@4725 ed5197a5-7fde-0310-b194-c3ffbd925b24

src/bip39.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+bool tf_bip39_bytes_to_words(const uint8_t* bytes, size_t bytes_size, char* out_words, size_t words_size);
+bool tf_bip39_words_to_bytes(const char* words, uint8_t* out_bytes, size_t bytes_size);