Change Scale#apply_intervals to Scale#to_pitches
Add Tempo class.
In Score class, replace beats_per_minute_profile and beat_duration_profile with tempo_profile.
Add Pitch.make_from_freq.
Add bin/transcribe to produce a musical part from an audio file.
Move ScoreCollator and ScoreConverter functionality into the Score class, via class reopening.
For Score#initialize, allow nil for :tempo_profile and :program. When :program is nil, the score covers all the parts (start to finish). When :tempo_profile is nil, the parts are all interpreted as being in a time base already (durations and offset in time, not notes).
Add :file_path option to Part#initialize, so a part can be loaded from a YAML file.
Fixed note duration in bin/transcribe, so part plays at normal speed.