Adding Maps page to page_sets for telemetry.

tools/perf/page_sets/data/top_25.json

 {
-    "description": "Describes the Web Page Replay archives for a page set. Don't edit by hand! Use record_wpr for updating.", 
+    "description": "Describes the Web Page Replay archives for a user story set. Don't edit by hand! Use record_wpr for updating.", 
     "archives": {
         "top_25_003.wpr": [
             "Facebook"
         ], 
         "top_25_001.wpr": [
             "https://plus.google.com/110031535020051778989/posts"
         ], 
         "top_25_002.wpr": [
             "https://www.google.com/search?q=cats&tbm=isch"
         ], 
@@ skipping 17 matching lines @@
             "http://www.weather.com/weather/right-now/Mountain+View+CA+94043", 
             "http://www.amazon.com", 
             "http://www.ebay.com", 
             "http://games.yahoo.com", 
             "http://booking.com", 
             "http://answers.yahoo.com", 
             "http://sports.yahoo.com/", 
             "http://techcrunch.com"
         ]
     }
-}
+}