feat(tracker/presets): improving and adding presets

tracker/presets/DR/Snare_808.yml

@@ -0,0 +1,21 @@
+numvoices: 1
+units:
+    - type: envelope
+      id: 1
+      parameters: {attack: 0, decay: 78, gain: 107, release: 0, stereo: 0, sustain: 0}
+    - type: oscillator
+      id: 2
+      parameters: {color: 64, detune: 64, gain: 73, looplength: 1, loopstart: 1578, phase: 0, samplestart: 176738, shape: 64, stereo: 0, transpose: 64, type: 4, unison: 0}
+    - type: filter
+      id: 1713
+      parameters: {bandpass: 1, frequency: 64, highpass: -1, lowpass: 0, resonance: 49, stereo: 0}
+      disabled: true
+    - type: mulp
+      id: 1701
+      parameters: {stereo: 0}
+    - type: pan
+      id: 5
+      parameters: {panning: 64, stereo: 0}
+    - type: outaux
+      id: 6
+      parameters: {auxgain: 4, outgain: 75, stereo: 1}