message: Fix buffer overflow.
diff: @@ -47,7 +47,7 @@ size_t BLE::sendMessage(const String &s)
  Serial.println("Message: '" + s + "'");
  - char buf[8];
  + char buf[16];
  sprintf(buf, "%02X %02X %02X %02X %02X %02X %02X", header.charAt(0), header.charAt(1), header.charAt(2), header.charAt(3), header.charAt(4), header.charAt(5), header.charAt(6));
  @@ -92,7 +92,7 @@ size_t BLE::recvMessage(String *s)
  msgSize = word(s->charAt(5), s->charAt(6));
  Serial.println("Length of message: '" + String(msgSize) + "'");
  - char buf[8];
  + char buf[16];
  sprintf(buf, "%02X %02X %02X %02X %02X %02X %02X", s->charAt(0), s->charAt(1), s->charAt(2), s->charAt(3), s->charAt(4), s->charAt(5), s->charAt(6));
  