Issue 66 fixed: PPM_LIMITS_SYMETRICAL Makefile option added (pls tell me if not the right name)

RSSI Tx and Rx before A1 and A2
Rotary Encoder on ersky9x board
A Mix may be defined in many Phases (idea from Romolo, thanks!)
Differential is now a Curve (private Curve of a Mix)
Issue 56 fixed (native stick as Mix input)
EEPROM saving (LimitData structure)
Issue 79 fixed (Audio Queue)
Trims now working in ersky9x simu

src/pulses_avr.cpp

@@ -213,7 +213,7 @@ void setupPulsesPPM(uint8_t proto)
     rest += (int32_t(g_model.ppmFrameLength))*1000;
     for (uint8_t i=(proto==PROTO_PPM16) ? p-8 : 0; i<p; i++) {
 #ifdef PPM_CENTER_ADJUSTABLE
-      int16_t v = limit((int16_t)-PPM_range, g_chans512[i], (int16_t)PPM_range) + 2*(PPM_CENTER+g_model.servoCenter[i]);
+      int16_t v = limit((int16_t)-PPM_range, g_chans512[i], (int16_t)PPM_range) + 2*(PPM_CENTER+limitaddress(i)->ppmCenter);
 #else
       int16_t v = limit((int16_t)-PPM_range, g_chans512[i], (int16_t)PPM_range) + 2*PPM_CENTER;
 #endif