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/DR/hihat-closed.yml

@@ -0,0 +1,30 @@
+name: hihat-closed
+numvoices: 1
+units:
+    - type: envelope
+      id: 1
+      parameters: {attack: 0, decay: 61, gain: 128, release: 0, stereo: 0, sustain: 0}
+    - type: envelope
+      id: 13
+      parameters: {attack: 28, decay: 60, gain: 94, release: 0, stereo: 0, sustain: 0}
+    - type: mulp
+      id: 14
+      parameters: {stereo: 0}
+    - type: noise
+      id: 2
+      parameters: {gain: 63, shape: 57, stereo: 0}
+    - type: mulp
+      id: 3
+      parameters: {stereo: 0}
+    - type: filter
+      id: 15
+      parameters: {bandpass: -1, frequency: 67, highpass: -1, lowpass: 0, resonance: 95, stereo: 0}
+    - type: filter
+      id: 4
+      parameters: {bandpass: -1, frequency: 109, highpass: 0, lowpass: 1, resonance: 55, stereo: 0}
+    - type: pan
+      id: 5
+      parameters: {panning: 64, stereo: 0}
+    - type: outaux
+      id: 6
+      parameters: {auxgain: 0, outgain: 48, stereo: 1}