Mellite - Tutorial - Part 5: Using the new Pattern abstraction

Introduction to the Mellite computer music environment. Part 5: Using the new Pattern abstraction. This is based on Mellite v2.22.0. See https://www.sciss.de/mellite/ for details. __Updates:__ 13:30 - as of Mellite v2.23.0, we use camel-case, so it's `midiCps` instead of `midicps` now.