version 0.2

So much new stuff!

• proper time units (milliseconds instead of sample points)
• separate per-channel controls
• open and close any window
• horizontal and vertical offset
• separate XY scope controls
  (maybe it's not that much...)

version 0.1

Hey I did it!
This version contains the "main" functions of an old-school oscilloscope, even if the implementations are quite primitive.
Timebase, vertical scale, triggering...
There's an XY oscilloscope, because why not!
And you can select which audio device to visualize.
And that's it!