Ignore blank lines in playlist -- fixes panic w/EXT-X-MAP.

[ejohnst]

reader.go panics if there's a blank line between the header containing EXT-X-MAP and the first segment for FMP4 media playlists. (It tries to add MAP to the first segment, which it hasn't created yet.)

Patch fixes this by ignoring blank lines; media-playlist-large-with-attributes.m3u8 sample playlist modified to recreate panic and reader_test.go updated to work with change (one of the tests assumed prior behavior) and test parsing of media-playlist-large-with-attributes.m3u8.

[tmm1]

Please send this upstream. This fork is not maintained for public use.

https://github.com/grafov/m3u8

[eric]

To confirm this is the correct behavior, the RFC states:

Lines in a Playlist file are terminated by either a single line feed
character or a carriage return character followed by a line feed
character. Each line is a URI, is blank, or starts with the
character '#'. Blank lines are ignored. Whitespace MUST NOT be
present, except for elements in which it is explicitly specified.

[eric]

This has been reported on: grafov#166

[ejohnst]

Wasn't sure if sending it upstream would be all that productive, so figured I'd start here. (I find your fork to be the most useful and Channels to be a great app.) Will try grafov/m3u8, though. Thanks!

[tmm1]

We've been able to upstream changes and will keep an eye on grafov#178