- The link establishment timeout is infinite by default
- Fix typo in notes about the auth kwarg

This file contains various MicroPython-specific helper functions, so isn't
good fit for lib/libc/.

This makes select.poll() interface fully compatible with CpYthon. Also, make
their numeric values of these options compatible with Linux (and by extension,
with iBCS2 standard, which jopefully means compatibility with other Unices too).

Port specific settinigs defined in mpconfigport. FreeRTOS and semphr
headers added to define SemaphoreHandle_t for the SYNC_T.

The default setting of using the "highest" method available doesn't
work with some servers like Microsoft Azure. TLSV1 seems to work with
pretty much any server.

This fixes paste mode (Ctrl-E) which was not working for the
telnet REPL.

py/mphal.h contains declarations for generic mp_hal_XXX functions, such
as stdio and delay/ticks, which ports should provide definitions for.  A
port will also provide mphalport.h with further HAL declarations.

Incluides several improvements and a few API changes to comply
with the new hardware API.

The UART REPL it's not enabled by default anymore.