readme: use normal links so they render on GitLab and PyPI

Features

--------

- `StructuredLogger <logstruct.StructuredLogger>` - a replacement for `logging.Logger`

  with a simplified interface for adding structured data to logs. (`Usage <logger_usage>`)

- `StructuredFormatter <logstruct.StructuredFormatter>` - a `logging.Formatter`

  implementation that formats log records as JSON. (`Usage <formatter_usage>`)

- `contextual information <context_usage>` to log records with `logstruct.context_scope`.

.. Do not use references other than links here, they will not render on PyPI or GitLab.

- `StructuredLogger <https://logstruct.readthedocs.io/stable/usage.html#logger-usage>`_ - a replacement

  for ``logging.Logger`` with a simplified interface for adding structured data to logs.

- `StructuredFormatter <https://logstruct.readthedocs.io/stable/usage.html#formatter-configuration>`_ - a

  ``logging.Formatter`` implementation that formats log records as JSON.

- `Contextual information <https://logstruct.readthedocs.io/stable/usage.html#context-variables>`_ added

  to all log records within ``logstruct.context_scope``.

- Easy to use and simple to configure, **no dependencies**.

- Seamlessly integrates with any code using stdlib `logging`, e.g. Sentry SDK.

- Human readable output for development - see `demo_dev_mode.py <dev_mode_logging>`.

- Will work with any tooling that integrates with stdlib ``logging``, e.g. Sentry SDK.

- `Human readable output <https://logstruct.readthedocs.io/stable/usage.html#development-mode-logging>`_

  for development.

Design principles

-----------------

    pdm lock -G :all

Tests are run with pytest and Sphinx’s `doctest` target.

Tests are run with pytest and Sphinx’s `doctest

<https://docs.python.org/3/library/doctest.html#module-doctest>`_ target.

.. code:: sh

.. _logger_usage:

.. _logging_structured_data:

Structured data

---------------

Logging structured data

-----------------------

`StructuredLogger <logstruct.StructuredLogger>`'s logging API is nearly identical to the standard

library `logging.Logger`. The key difference is that additional **keyword arguments** provided to

the standard library.

.. _formatter_usage:

.. _formatter_configuration:

Formatter configuration

^^^^^^^^^^^^^^^^^^^^^^^