Tiny Filament Sensor - Optical version

Tiny Filament Sensor - Optical Version
using Tiny Photoelectric Sensor

/**
* Filament Runout Sensors
* Mechanical or opto endstops are used to check for the presence of filament.
*
* RAMPS-based boards use SERVO3_PIN for the first runout sensor.
* For other boards you may need to define FIL_RUNOUT_PIN, FIL_RUNOUT2_PIN, etc.
* By default the firmware assumes HIGH=FILAMENT PRESENT.
*/
//#define FILAMENT_RUNOUT_SENSOR