Added "GET list subscriptions" api method

lib/twitter/base.rb

@@ -224,6 +224,10 @@ def list_subscribe(list_owner_username, slug)
     def list_unsubscribe(list_owner_username, slug)
       perform_delete("/#{list_owner_username}/#{slug}/subscribers.json")
     end
+
+    def list_subscriptions(list_owner_username)
+      perform_get("/#{list_owner_username}/lists/subscriptions.json")
+    end
 
     private
       def perform_get(path, options={})

test/fixtures/list_subscriptions.json

@@ -0,0 +1 @@
+{"lists":[{"mode":"public","uri":"/chriseppstein/sass-users","member_count":28,"slug":"sass-users","full_name":"@chriseppstein/sass-users","user":{"statuses_count":2102,"profile_link_color":"1F98C7","description":"Father, Software Engineer, Drinker of Beer","profile_background_tile":false,"geo_enabled":false,"profile_background_color":"C6E2EE","following":false,"verified":false,"profile_sidebar_fill_color":"DAECF4","followers_count":394,"time_zone":"Pacific Time (US & Canada)","profile_sidebar_border_color":"C6E2EE","url":null,"profile_image_url":"http://a1.twimg.com/profile_images/51769630/Photo_5_normal.jpg","created_at":"Fri Mar 14 17:33:06 +0000 2008","friends_count":106,"protected":false,"location":"San Jose, CA","screen_name":"chriseppstein","name":"Chris Eppstein","notifications":false,"favourites_count":80,"profile_text_color":"663B12","id":14148091,"profile_background_image_url":"http://s.twimg.com/a/1257191498/images/themes/theme2/bg.gif","utc_offset":-28800},"name":"sass-users","subscriber_count":8,"id":1680857}], "next_cursor":0, "previous_cursor":0 }

test/twitter/base_test.rb

@@ -199,6 +199,14 @@ class BaseTest < Test::Unit::TestCase
         user.screen_name.should == 'jnunemaker'
       end
 
+      should "be able to view a members list subscriptions" do
+        stub_get('/pengwynn/lists/subscriptions.json', 'list_subscriptions.json')
+        subscriptions = @twitter.list_subscriptions('pengwynn').lists
+        subscriptions.size.should == 1
+        subscriptions.first.full_name.should == '@chriseppstein/sass-users'
+        subscriptions.first.slug.should == 'sass-users'
+      end
+
     end