Release 2020.1

• upgraded POCO to release 1.10.1
• updated OSP and Remoting frameworks (see their respective release notes for details)
• modernized codebase to use C++14
• JavaScript: fixed an unhandled exception in RecordSet.toJSON() if record set is empty
• JavaScript: fixed potential memory leaks due to wrong v8::Persistent use in
  some places
• JavaScript: optimized handling of timer callbacks to avoid excessive delays when
  stopping a script with 10000s of timers
• Bluetooth support (BtLE) has been upgraded to work with current versions
  of bluepy-helper
• BtLE: it's now possible create basic Peripheral devices and use them from JavaScript
• Modbus: added ModbusMaster::reset() method
• added device interface for cameras
• various minor improvements and fixes