[Key module] Analyze a chord in a Key

[danigb]

Something like:

Key.analyzeChord('C', 'Cmaj7');
[{ 
  key: 'C major',  
  chord: 'CMaj7', 
  harmonicFunction: 'T', 
  scale: 'major', 
  degree: 1 
}]

[martijnmichel]

This would be great!