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Added:
* Add ``RequiredConfigMixin.get_runtime_config()`` which returns the runtime
configuration for a component or tree of components. This lets you print
runtime configuration at startup, generate INI files, etc.
* Add ``ConfigObjEnv`` which lets you use an object for configuration. This
works with argparse's Namespace amongst other things.
Changed:
* Change ``:show-docstring:`` to take an optional value which is the attribute
to pull docstring content from. This means you don't have to mix programming
documentation with user documentation--they can be in different attributes.
* Improve configuration-related exceptions. With Python 3, configuration errors
all derive from ``ConfigurationError`` and have helpful error messages that
should make it clear what's wrong with the configuration value. With Python 2,
you can get other kinds of Exceptions thrown depending on the parser used, but
configuration error messages should still be helpful.
Documentation fixes and updates.