upgrade browserify-sign to use determanistic k

Author: calvinmetcalf

package.json

@@ -19,7 +19,7 @@
     "browserify-aes": "0.8.1",
     "create-ecdh": "1.0.3",
     "diffie-hellman": "2.2.3",
-    "browserify-sign": "2.7.5",
+    "browserify-sign": "2.8.0",
     "pbkdf2-compat": "2.0.1",
     "public-encrypt": "1.1.2",
     "ripemd160": "0.2.0",