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.
Rename FrameBuffer1 into FrameBuffer and make it handle different bit
depths via a method table that has getpixel and setpixel. Currently
supported formats are MVLSB (monochrome, vertical, LSB) and RGB565.
Also add blit() and fill_rect() methods.