6. A.L.tr Amplitude LFO trigger

Defines what should happen to the oscillator's amplitude LFO ("Low Frequency Oscillator") when a new note is triggered;

• 'FrEE' will not cause the LFO to restart
• 'Retr' will cause the LFO to restart
• 'Cond' will only cause the LFO to engage if the step that triggered the note has a valid ('when') 'ALFO' condition ('do') set
• 'rand' will start the LFO at a random phase (location in the chosen waveform)