Fix more Teensy LC warnings

https://forum.pjrc.com/threads/60488?p=269918&viewfull=1#post269918

https://forum.pjrc.com/threads/60488?p=269748&viewfull=1#post269748

https://forum.pjrc.com/threads/60488-Porting-moog-ladder-filters-to-audio-objects

wav2sketch.js Add PROGMEM to output array

Wav2sketch js

Switch headphone source between input and DAC

Round down to 0 to avoid the buzzing noise issue

Fix phase modulation

AudioPlaySdWav Feature: togglePlayPause

AsyncAudioInputSPDIF3 minor bug fix/clipping prevention

sg5k: calcBiquad: add missing break; for hishelf

Add Teensy LC Code for PT8211

Add SGTl5000 MasterMode

Teensy LC AudioOutputI2S(+slave)

Fixes for Teensy LC

Fix documentation for SGTL lineInLevel (swap channels)

Update index.html

Band limited waveforms

MQS: Play nice

keeps 352kHZ PWM, but reduces hardware-oversampling to 32x

changed
{"type":"AudioOutputPWM",        "resource":"DAC1",           "shareable":false},
to
{"type":"AudioOutputPWM",        "resource":"PWM",           "shareable":false},

Attention this last part is *untested*

TBD: input as "Master". Do we need this?

Change delay(5) to delay(25)

Slavemode tested,
TODO: Test Mastermode (PCCM1802?)
TODO: Input

This adds a new enable() function.

bool enable(extMCLK, pllFreq);
switches the SGTL to Master Mode.

On LC this done automatically, so the normal enable() works with the Teensy LC.

Needed for Blocksize=128.
Blocksize 128 is needed for the waveplayer

There was a missing `break;` at the end of the FILTER_HISHELF
case in the calculations, meaning a hishelf coeff calc always
returned the default fallthrough case, which is a benign passthrough
filter.

Fix by adding the `break;`.

Fixes: #343

Signed-off-by: Graham Whaley <graham.whaley@gmail.com>