The individual union members (like SPI, I2C) are never used, only the
generic "reg" entry is. And the union names can clash with macro
definitions in the HAL so better to remove them.
This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.
Converts generted pins to use qstrs instead of string pointers.
This patch also adds the following functions:
pyb.Pin.names()
pyb.Pin.af_list()
pyb.Pin.gpio()
dir(pyb.Pin.board) and dir(pyb.Pin.cpu) also produce useful results.
pyb.Pin now takes kw args.
pyb.Pin.__str__ now prints more useful information about the pin
configuration.
I found the following functions in my boot.py to be useful:
```python
def pins():
for pin_name in dir(pyb.Pin.board):
pin = pyb.Pin(pin_name)
print('{:10s} {:s}'.format(pin_name, str(pin)))
def af():
for pin_name in dir(pyb.Pin.board):
pin = pyb.Pin(pin_name)
print('{:10s} {:s}'.format(pin_name, str(pin.af_list())))
```