Expand node version compatibility

Previously the library could not be installed with node 12:

https://github.com/ripple/ripple-binary-codec/pull/33

package.json

@@ -24,8 +24,8 @@
     "jsonschema": "1.2.2",
     "lodash": "^4.17.4",
     "ripple-address-codec": "^3.0.4",
-    "ripple-binary-codec": "0.2.2",
-    "ripple-hashes": "0.3.2",
+    "ripple-binary-codec": "^0.2.4",
+    "ripple-hashes": "^0.3.4",
     "ripple-keypairs": "^0.10.1",
     "ripple-lib-transactionparser": "0.7.1",
     "ws": "^3.3.1"