Add simple huffman tree test

tests/test_decode_huffman_tree.c

@@ -0,0 +1,13 @@
+#include <stdio.h>
+#include <strings.h>
+
+#include "libmineziper_huffman_tree.h"
+#include "libmineziper_zip.h"
+
+int main(int argc, char** argv)
+{
+  tree def = build_default_tree();
+  print_huffman_tree(def);
+
+  return 0;
+}