Add inline preview of Twitter links.

This uses the unauthed v1 of the Twitter API, which is going to go
away soon, but it's fine as an interim measure.

(imported from commit 709a250271321f5479854a363875c9da43e6382d)

zephyr/lib/bugdown/testing_mocks.py

@@ -0,0 +1,63 @@
+
+import simplejson
+
+def twitter(tweet_id):
+    return simplejson.loads("""{
+  "coordinates": null,
+  "created_at": "Sat Sep 10 22:23:38 +0000 2011",
+  "truncated": false,
+  "favorited": false,
+  "id_str": "112652479837110273",
+  "in_reply_to_user_id_str": "783214",
+  "text": "@twitter meets @seepicturely at #tcdisrupt cc.@boscomonkey @episod http://t.co/6J2EgYM",
+  "contributors": null,
+  "id": 112652479837110273,
+  "retweet_count": 0,
+  "in_reply_to_status_id_str": null,
+  "geo": null,
+  "retweeted": false,
+  "possibly_sensitive": false,
+  "in_reply_to_user_id": 783214,
+  "user": {
+    "profile_sidebar_border_color": "eeeeee",
+    "profile_background_tile": true,
+    "profile_sidebar_fill_color": "efefef",
+    "name": "Eoin McMillan ",
+    "profile_image_url": "http://a1.twimg.com/profile_images/1380912173/Screen_shot_2011-06-03_at_7.35.36_PM_normal.png",
+    "created_at": "Mon May 16 20:07:59 +0000 2011",
+    "location": "Twitter",
+    "profile_link_color": "009999",
+    "follow_request_sent": null,
+    "is_translator": false,
+    "id_str": "299862462",
+    "favourites_count": 0,
+    "default_profile": false,
+    "url": "http://www.eoin.me",
+    "contributors_enabled": false,
+    "id": 299862462,
+    "utc_offset": null,
+    "profile_image_url_https": "https://si0.twimg.com/profile_images/1380912173/Screen_shot_2011-06-03_at_7.35.36_PM_normal.png",
+    "profile_use_background_image": true,
+    "listed_count": 0,
+    "followers_count": 9,
+    "lang": "en",
+    "profile_text_color": "333333",
+    "protected": false,
+    "profile_background_image_url_https": "https://si0.twimg.com/images/themes/theme14/bg.gif",
+    "description": "Eoin's photography account. See @mceoin for tweets.",
+    "geo_enabled": false,
+    "verified": false,
+    "profile_background_color": "131516",
+    "time_zone": null,
+    "notifications": null,
+    "statuses_count": 255,
+    "friends_count": 0,
+    "default_profile_image": false,
+    "profile_background_image_url": "http://a1.twimg.com/images/themes/theme14/bg.gif",
+    "screen_name": "imeoin",
+    "following": null,
+    "show_all_inline_media": false
+  },
+  "in_reply_to_screen_name": "twitter",
+  "in_reply_to_status_id": null
+}""")