ammend note about begin (closes #219)

README.md

@@ -28,7 +28,7 @@ Attempts to download a video from the given url. Returns a readable stream. `opt
 * `filter` - Can be `video` to filter for formats that contain video, `videoonly` for formats that contain video and no additional audio track. Can also be `audio` or `audioonly`. You can give a filtering function that gets called with each format available. Used to decide what format to download. This function is given the `format` object as its first argument, and should return true if the format is preferable.
 * `format` - This can be a specific `format` object returned from `getInfo`. This is primarily used to download specific video or audio streams. Note: Supplying this option will ignore the `filter` and `quality` options since the format is explicitly provided.
 * `range` - A byte range in the form `{start: INT, end: INT}` that specifies part of the file to download. ie {start: 10355705, end: 12452856}. Note: this downloads a portion of the file, and not a separately spliced video.
-* `begin` - What time to begin downloading the video, supports formats 00:00:00.000, or 0ms, 0s, 0m, 0h, or number of milliseconds. Example: 1:30, 05:10.123, 10m30s. This option may not work on super short (less than 30s) videos, and has to be at or above 6s. See [#129](https://github.com/fent/node-ytdl-core/issues/129)
+* `begin` - What time to begin downloading the video, supports formats 00:00:00.000, or 0ms, 0s, 0m, 0h, or number of milliseconds. Example: 1:30, 05:10.123, 10m30s. This option may not work on super short (less than 30s) videos, and has to be at or above 6s, see [#129](https://github.com/fent/node-ytdl-core/issues/129). It may also not work for some formats, see [#219](https://github.com/fent/node-ytdl-core/issues/219).
 * `requestOptions` - Anything to merge into the request options which [miniget](https://github.com/fent/node-miniget) is called with, such as headers.
 * `highWaterMark` - How much of the video download to buffer into memory. See [node's docs](https://nodejs.org/api/stream.html#stream_constructor_new_stream_writable_options) for more.
 * `retries` - The number of retries ytdl is allowed to do before terminating the stream with an error. The default is set to 5.