Refactor out reusable pieces from new Botlist

appengine/swarming/elements/res/imp/botlist/bot-list-data.html

 <!--
   Copyright 2016 The LUCI Authors. All rights reserved.
   Use of this source code is governed under the Apache License, Version 2.0
   that can be found in the LICENSE file.
 
   This in an HTML Import-able file that contains the definition
   of the following elements:
 
     <bot-list-data>
 
@@ skipping 12 matching lines @@
         server-side.  This can have dimensions:Array<String>, quarantined:String
         and is_dead: String. For example:
         {
           "dimensions": ["pool:Skia", "device_type:Sprout"],
           "quarantined": "FALSE",  // optional
           "is_dead": "TRUE",       // optional
         }
         For a full list of dimensions in the fleet, see the API call:
         https://[swarming_url]/_ah/api/swarming/v1/bots/dimensions
     // outputs
-    bots: Array<Object>, all bots returned by the botlist.  This is an Object
+    bots: Array<Object>, all bots returned by the server.  This is an Object
         with at least the following structure:
       dimensions: Array<Object>: Has key:String and value:Array<String>
       task_id: String
       external_ip: String
       is_dead: Object: Is usually Boolean, but could be message string
       quarantined: Object: Is usually Boolean, but could be message string
       bot_id: String
       state: String, Stringified JSON that has many pieces of information, like
                 devices, disk space, temperature, etc.
     busy: Boolean, if any ajax requests are in flight.
@@ skipping 234 matching lines @@
 
         // No need to sort any of this, bot-filters sorts secondary items
         // automatically, especially when the user types a query.
         return pMap;
       },
 
     });
   })();
   </script>
 </dom-module>