saugns v0.4.7. Improved named note frequencies. Language changes: * Add generator type `A` (Amplitude generator), for sweepable amplitude offsets i.e. DC offsets, plus adding and/or multiplying its AM modulators. * Frequencies as notes. - Support MIDI note number constants (`M0` to `M127` where `M69` by default corresponds to 440 Hz). All tuning systems are supported, but for just intoned notes, numbers which don't map to any natural note get the average of the two surrounding ones. Other options include flats and sharps (which for a just note are never exactly between two notes) like for C-D-E-F-G-A-B notes. - For just intoned tuning modes, rotate scale ratios with key selection, so that the note for a key has the first ratio. Makes tuning good for non-C keys. Generator `A` is yet of limited use, but will take a greater role when distortion options etc. are added.