Previously a child logger just uses the global default when unset.
Modified to matches the CPython behavior of using the parent's level.
Also implemented CPython's getEffectiveLevel() which provides a convenient
way to implement this. In our version, we only ever have one parent
(the root), so it only has to recurse one level.
Also set the default level to WARNING to match CPython.
Updated the examples to highlight the differences (but they now match).
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Add support for all format specifiers, support for `datefmt` using
(optional) strftime, and support for Stream and File handlers.
Ports/boards that need to use `FileHandlers` should enable
`MICROPY_PY_SYS_ATEXIT`, and enabled `MICROPY_PY_SYS_EXC_INFO` if using
`logging.exception()`.
Jim Mussared