Update timezone lookup to use offline method instead of Google API

package.json

@@ -7,23 +7,23 @@
     "test": "mocha test"
   },
   "dependencies": {
-    "cron": "^1.0.9",
+    "cron": "^1.3.0",
     "dotenv": "^2.0.0",
-    "express": "^4.13.0",
-    "grunt": "^1.0.1",
-    "moment-timezone": "^0.5.4",
-    "mongoose": "^4.0.6",
-    "suncalc": "^1.6.0",
-    "timezoner": "^0.1.9",
-    "xml2js": "^0.4.9"
+    "express": "^4.16.3",
+    "geo-tz": "^4.0.1",
+    "grunt": "^1.0.2",
+    "moment-timezone": "^0.5.17",
+    "mongoose": "^4.13.13",
+    "suncalc": "^1.8.0",
+    "xml2js": "^0.4.19"
   },
   "devDependencies": {
     "chai": "^3.0.0",
     "codecov.io": "^0.1.5",
-    "grunt-contrib-jshint": "^1.0.0",
-    "hippie": "^0.5.0",
-    "istanbul": "^0.4.3",
-    "mocha": "^2.2.5",
-    "nock": "^8.0.0"
+    "grunt-contrib-jshint": "^1.1.0",
+    "hippie": "^0.5.1",
+    "istanbul": "^0.4.5",
+    "mocha": "^5.2.0",
+    "nock": "^9.2.6"
   }
 }