Fix #30: allow disabling resampling for decodeAudioData

[rtoy]

Add yet another optional dictionary parameter to decodeAudioData to
allow disabling the resampling for decodeAudioData.

Defines a new dictionary for these options.

Links and processing model updated appropriately.

[joeberkovitz]

@rtoy I assume we'd put this off given the recent WG resolution to table temporary fixes to decodeAudioData. Perhaps the best sort of band-aid solution is to tack on yet another optional argument to the current method?

[rtoy]

Yes, after last week's teleconf, I assumed this would be postponed to v.next. If we do want to continue with this (and the progress callback), another optional argument would be ok. This argument would be a dictionary.

Perhaps this needs to be discussed further by the WG?

[rtoy]

Closing this pull request; we'll revisit this later in a future design of decodeAudioData