Fix issue with minor and no key analysis

This PR addresses two issues:

1. Make sure that the minor scale degrees table is being used for analysis (iDegrees is for minor keys and jDegrees is for major keys).
2. Make sure that *scale degree* and *solfege* analysis is **not** done when the key signature is set to "no key" because it doesn't make sense in that context.

There is also some minor refactoring in this PR, but all of it related to the first two items.