Add Note.major, .minor getters that return a Tonality

[albertms10]

Description

• Add .major and .minor getters to the Note class.
• (optional) Replace static constant constructors with these getters.

Example

Before:

const tonality1 = Tonality(BaseNote.fSharp, TonalMode.major)
const tonality2 = Tonality.dMinor

After:

final tonality1 = Note.fSharp.major
final tonality2 = Note.d.minor

Advantages

• More expressive API.
• Can express any argument combination for a Tonality instance without declaring specific static constant constructors.

Drawbacks

• Cannot be used in constant contexts.

Acknowledgements

@plammens for suggesting the change.