Allow autobaud from min to max

TinyGsmCommon.h

@@ -72,12 +72,14 @@ const T& TinyGsmMax(const T& a, const T& b)
 }
 
 template<class T>
-uint32_t TinyGsmAutoBaud(T& SerialAT)
+uint32_t TinyGsmAutoBaud(T& SerialAT, uint32_t minimum = 9600, uint32_t maximum = 115200)
 {
   static uint32_t rates[] = { 115200, 57600, 38400, 19200, 9600, 74400, 74880, 230400, 460800, 2400, 4800, 14400, 28800 };
 
   for (unsigned i = 0; i < sizeof(rates)/sizeof(rates[0]); i++) {
     uint32_t rate = rates[i];
+    if (rate < minimum || rate > maximum) continue;
+
     DBG("Trying baud rate", rate, "...");
     SerialAT.begin(rate);
     delay(10);