[v1.20.0.rc10] Release Candidate

### Bug fixes
- Fix for class C downlink data in LoRa ABP mode
- Updated adv config to split info between adv packet and scan response in BLE
- Increased Lora Timer task stack size

### Improvements
- Added support for LoRa Class C multicast
- Updated Char max length to correspond to MTU #279

esp32/pycom_version.h

@@ -10,7 +10,7 @@
 #ifndef VERSION_H_
 #define VERSION_H_
 
-#define SW_VERSION_NUMBER                              "1.20.0.rc9"
+#define SW_VERSION_NUMBER                              "1.20.0.rc10"
 
 #define LORAWAN_VERSION_NUMBER                         "1.0.2"