Replace "master" with "controller" and "slave" with "peripheral" in
comments, errors, and debug messages.
Add CONTROLLER and PERIPHERAL constants to pyb.SPI and pyb.I2C classes;
retain MASTER and SLAVE constants for backward compatiblity.
This adds the Python files in the tests/ directory to be formatted with
./tools/codeformat.py. The basics/ subdirectory is excluded for now so we
aren't changing too much at once.
In a few places `# fmt: off`/`# fmt: on` was used where the code had
special formatting for readability or where the test was actually testing
the specific formatting.
A few tests still fail on PYBLITE, and that's due to differences in the
available peripheral block numbers on the different MCUs (eg I2C(2)
exists on one, but it's I2C(3) on the other).
