I made some updates for the &saw music sequencer

• UI rework. New font and icons, and now it works with touch screen as well as with mouse and keyboard.
• Sampler instrument. You can drag & drop a WAV file and use it for the sampler. Also works in browser.
• Microtonal tuning for the music sheet. Now you can see exact frequency of each note in the UI, and there is two tuning modes: equal temperament (pen icon), pythagorean tuning (feather icon). This is temporary until I implement the complete tuning UI. Also, you can directly edit note frequencies in the project file, which is just plain text.

Here is a quick demo drum beat; and an example of how the same 5th interval sounds in different tuning modes. You can hear that in the pythagorean tuning there is no interference; in the equal temperament tuning there is very little interference; and the last one is "wolf fifth" with a lot of interference - worst case of the pythagorean tuning.