Currently, ChordAnalyser only accepts scales for its input, which is inconsistent with ChordRomanConverter which can accept keys. Allow ChordAnalyser to accepts keys as well in its analysing methods.
Will be included in #39. By default, the analyser should only accept keys rather than scales since that makes more sense musically (analyse a chord against the key signature, rather than against a scale).
Currently, ChordAnalyser only accepts scales for its input, which is inconsistent with ChordRomanConverter which can accept keys. Allow ChordAnalyser to accepts keys as well in its analysing methods.