feat!: display the parameters as knobs in a grid

Also removed the negbandpass & neghighpass parameters
and replaced them with bandpass & highpass set to -1, to
fit the switches better to the GUI.

Closes #51, closes #173

tracker/presets/SY/guitar2.yml

@@ -1,9 +1,9 @@
-name: Guitar2
+name: guitar2
 numvoices: 1
 units:
-    - type: envelope
-      id: 1
-      parameters: {attack: 0, decay: 0, gain: 70, release: 72, stereo: 0, sustain: 128}
+    - id: 87
+      parameters: {}
+      comment: Karplus-Strong
     - type: envelope
       id: 2
       parameters: {attack: 0, decay: 58, gain: 69, release: 0, stereo: 0, sustain: 0}
@@ -13,19 +13,22 @@ units:
     - type: mulp
       id: 4
       parameters: {stereo: 0}
-    - type: filter
-      id: 5
-      parameters: {bandpass: 1, frequency: 30, highpass: 1, lowpass: 1, negbandpass: 0, neghighpass: 0, resonance: 128, stereo: 0}
     - type: delay
       id: 6
       parameters: {damp: 16, dry: 128, feedback: 128, notetracking: 1, pregain: 128, stereo: 0}
       varargs: [10787]
-    - type: filter
-      id: 84
-      parameters: {bandpass: 1, frequency: 24, highpass: 1, lowpass: 1, negbandpass: 0, neghighpass: 0, resonance: 128, stereo: 0}
+    - id: 88
+      parameters: {}
+      comment: Main envelope
+    - type: envelope
+      id: 1
+      parameters: {attack: 0, decay: 0, gain: 70, release: 72, stereo: 0, sustain: 128}
     - type: mulp
       id: 85
       parameters: {stereo: 0}
+    - id: 89
+      parameters: {}
+      comment: Output
     - type: pan
       id: 86
       parameters: {panning: 64, stereo: 0}