Fix package name in package.json

It was noted in an email to security@ that this package name was wrong and not registered on NPM, which could be an issue if the wrong name was used elsewhere and maliciously registered.

Author: area

package.json

@@ -1,5 +1,5 @@
 {
-  "name": "@colony.io/colony-network-contracts",
+  "name": "@colony/colony-network-contracts",
   "version": "1.0.0",
   "description": "Contracts for Colony Network",
   "engines": {