Added code for silicone printing and minor tweaks.

* Turned on debug for accelerometer demo.

* Added code for SSR switch  used to control pressure regulator for
silicone printing.
Fixed issue with random disconnections.

* Issue was fixed by switching the software serial library from
“SoftwareSerial” to “AltSoftSerial”.

* new library has the caveat of only working on pins 8 & 9. It also
rendered PWM on pin 10 useless. Documentation on this can be found
here: https://www.pjrc.com/teensy/td_libs_AltSoftSerial.html

NOTE: AltSoftSerial