Add repository field

Author: dandv

package.json

@@ -12,6 +12,10 @@
   "scripts": {
     "build": "gulp build"
   },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/HubSpot/tether.git"
+  },
   "license": "MIT",
   "main": "dist/js/tether.js",
   "devDependencies": {