Improved native codegen, better printf, support for F401 and F411 MCUs. py core: - implement delete for property and descriptors - add option to disable "enumerate" and "reversed" builtins - can call functions with *args in native emitter - implement full function arg passing for native emitter - combine load_attr and store_attr internal type methods into one - fix formatting of floating point numbers near 1.0 - support assignment of bytes to bytearray slices - overhaul and simplify printf/pfenv mechanism - fix builtin ord so that it can handle bytes values >= 0x80 - inlinethumb: add support for core floating point instructions - make viper code generator raise ViperTypeError on error lib: - string0.c now in lib/libc/ (was in stmhal/) - fatfs code size reduced (by 768 bytes on Thumb2 archs) tests: - more tests for builtins - tests for lexer - coverage increased to 93% stmhal: - make LED object print LED(x) for consistency with constructor - in USB HID driver, make polling interval configurable - allow sending CAN messages with timeout=0 - add support for sending and receiving CAN RTR messages - make board parameters more configurable (HSE PLL, LED4, TIMs, etc) - add support for F401 and F411 MCUs - add support for Espruino Pico board - make raw REPL mode 8-bit clean cc3200 port: - enable pull-ups for stdio UART pins - enable long filename support in fatfs - add WLAN.config_ip(), to assign a static IP - add IPPROTO_SEC so secure sockets can be made tools: - make pyboard.py 8-bit clean, so it works with unicode chars docs: - document pyb.main() function