OnStep lite replacement board for EQ 6 Pro

OnStep lite board for EQ 6 Pro on base Howard Dutton [project](https://onstep.groups.io/g/main/wiki/3860) Key properties: * Easy replacement of the original Synscan board (four screws and reconnect three wires) * Tennsy4.0 (or 3.2) CPU mainboard MiniPCB pin maps compatible * Big USB B port is very well working with ZWO ASiair * Bluetooth or Wi-Fi module * Internal real time clock with battery backup (need add 32.468 khz crystal to teensy 3.2 board) Advance features: * Port for polar scope iluminator * Internal DSLR timer * 8V2 power port for DSLR * Buzzer Wiring diagram and PCB are on [EasyEDA](https://easyeda.com/hujer.roman/onstep-eq6-simple). For enable advance feature requires the following minor modifications MiniPCB.h

#define ReticlePin           23  //   Aux4     // Drain
#define TonePin           Aux3 //   29         // Tone

For EQ6 recommended upgrade to [Rowan Engineering timing belt set](https://www.teleskop-express.de/shop/product_info.php/info/p7043)