Hardening Ogg parsing

Address issue #62: "FourCC contains invalid characters"

Fix multiple issues in ASF parser

• issue #57: embedded picture data, from a wma audio file, is accessible via the common metadata interface
• Fixed extended header iteration, causing potential headers (atoms) to be skipped.
• issue #61: correction ASF Compatibility GUID (had no runtime impact)

Fix RIFF-header & empty peak-volume

Fixes:

• #56 mp3 parsing results in 'RangeError: Index out of range', caused by empty PeakVolume tag
• #59 Bug in RIFF header decoding

Handle slash value separator according to ID3v2.3 specification

• Fix issue #52

Moved special tag handling to native-tag-implementation

Merge pull request #51 from Borewit/refactor/generic-tag-mapping

Refactor/generic tag mapping: Distribute mapping functionality among tag-format implementations.

Fix comment mapping

• Fix issue #50: Mapping ID3v2 comment mapping
• Fix reading iTunes/MP4/©cmt (comment field)
• Map iTunes/MP4/'----:com.apple.iTunes:NOTES' to comments
• Update dependencies

Remove unused dependency

Minor code style changes

Fix compatibility with readable-stream

Caused by instanceof check in then-read-stream
Ref:

• Borewit/peek-readable#4
• webtorrent/webtorrent-desktop#1320

Added Ogg/Opus support

Refactored Ogg parser to send Ogg pages instead of stream to the underlying coded (currently Vorbis & Opus).
Addresses issue #47.

Fix UTF-8 decoding in ogg vorbis tags

Issue #46, fixed by @felamaslen