v2.20

The first release in 22 years! Which was really just to get the build process up and running. But I could not resist changing a few things that bothered me:

• tracker screen cleaned up (zeroes suppressed) and now default screen
• sample details cleaned up (suppress loop information when there is none)
• saa1099 volume tables are calculated at 3 bits instead of 4 (not that it makes a difference)
• changing volume % only updates indicator when it is visible