Do not use format string "%0.3f" for RTSP Range field.

Fixes ticket 10.
The format string was locale-depending.

libavformat/rtspdec.c

@@ -59,9 +59,14 @@ static int rtsp_read_play(AVFormatContext *s)
         if (rt->state == RTSP_STATE_PAUSED) {
             cmd[0] = 0;
         } else {
-            snprintf(cmd, sizeof(cmd),
-                     "Range: npt=%0.3f-\r\n",
-                     (double)rt->seek_timestamp / AV_TIME_BASE);
+            if (!rt->seek_timestamp) {
+                snprintf(cmd, sizeof(cmd), "Range: npt=0.000-\r\n");
+            } else {
+                snprintf(cmd, sizeof(cmd),
+                         "Range: npt=%"PRId64".%03"PRId64"-\r\n",
+                         rt->seek_timestamp / AV_TIME_BASE,
+                         rt->seek_timestamp / (AV_TIME_BASE / 1000) % 1000);
+            }
         }
         ff_rtsp_send_cmd(s, "PLAY", rt->control_uri, cmd, reply, NULL);
         if (reply->status_code != RTSP_STATUS_OK) {