When running under mono, WebClient will sometimes return less data

than it should. This causes the FetchFeedService to log errors
because the XML received cannot be parsed. Setting the
AutomaticDecompression property on the WebRequest fixes this issue.

src/NzbDrone.Common/Http/HttpProvider.cs

@@ -22,6 +22,16 @@ namespace NzbDrone.Common.Http
 
     public class HttpProvider : IHttpProvider
     {
+        private class GZipWebClient : WebClient
+        {
+            protected override WebRequest GetWebRequest(Uri address)
+            {
+                HttpWebRequest request = (HttpWebRequest)base.GetWebRequest(address);
+                request.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
+                return request;
+            }
+        }
+
         private readonly Logger _logger;
 
         public const string CONTENT_LENGTH_HEADER = "Content-Length";
@@ -49,7 +59,7 @@ namespace NzbDrone.Common.Http
         {
             try
             {
-                var client = new WebClient { Credentials = identity };
+                var client = new GZipWebClient { Credentials = identity };
                 client.Headers.Add(HttpRequestHeader.UserAgent, _userAgent);
                 return client.DownloadString(url);
             }
@@ -107,7 +117,7 @@ namespace NzbDrone.Common.Http
                 _logger.Debug("Downloading [{0}] to [{1}]", url, fileName);
 
                 var stopWatch = Stopwatch.StartNew();
-                var webClient = new WebClient();
+                var webClient = new GZipWebClient();
                 webClient.Headers.Add(HttpRequestHeader.UserAgent, _userAgent);
                 webClient.DownloadFile(url, fileName);
                 stopWatch.Stop();