Remove internal network support

This commit removes the "old" networking code in favor of libavformat's
code.

The code was still used for mp_http, udp, ftp, cddb. http has been
mapped to libavformat's http support since approximately 6 months ago.
udp and ftp have support in ffmpeg (though ftp was added only last
month). cddb support is removed with this commit - it's probably not
important and rarely used if at all, so we don't care about it.

stream/stream_lavf.c

@@ -28,7 +28,6 @@
 #include "core/m_struct.h"
 #include "demux/demux.h"
 
-#include "network.h"
 #include "cookies.h"
 
 #include "core/bstr.h"
@@ -317,7 +316,7 @@ const stream_info_t stream_info_ffmpeg = {
   "",
   open_f,
   { "lavf", "ffmpeg", "rtmp", "rtsp", "http", "https", "mms", "mmst", "mmsh",
-    "mmshttp", NULL },
+    "mmshttp", "udp", "ftp", NULL },
   NULL,
   1 // Urls are an option string
 };