Added a more sophisticated json loading interface

- this should provide more verbose output in the case that the json file
  either doesn't exist or isn't formatted correctly

app.py

@@ -32,10 +32,21 @@ structure:
 import chevron
 import requests
 import json
+from os import path
 from pprint import pprint
 from flask import Flask, request
 
-stream_data = json.load(open('resources/data.json', 'r'))
+# load json data, or raise exception.
+if path.exists('resources/data.json'):
+    try:
+        stream_data = json.load(open('resources/data.json', 'r'))
+    except json.JSONDecodeError as e:
+        raise RuntimeError('JSON data did not pass validation.')
+else:
+    raise RuntimeError('Could not find ./resources/data.json, required for '
+                       'runtime!')
+
+# initialize requests session
 session = requests.Session()
 session.auth = ('admin', stream_data['stream_key'])