Hop timeout change

[spleenware]

Hi,

I tried a small change to the receiver, when calculating a missed hop, and seems to improve the time to 'recover' and get back in sync. In LoraRC.ino, here's the patch:

       #endif
     RX_last_frame_received = millis();

•    RX_hopping_time = micros()  + (TX_period * 2);
  

•    RX_hopping_time = micros()  + (TX_period * 3 /2);
     if (RX_RSSI < power_thr_low && power_delay_counter-- == 0) {
       power_increase();
       power_delay_counter = TX_POWER_DELAY_FILTER;