Magiconfig

* fix bug to allow calling `set_config_options()` if `config_options` were not initially provided when initializing the parser
* add function `copy_config_options()`
* update documentation

Second major release with modifications to the API, new features, and improvements:
* improved handling of config-only arguments:
* new accessors `add_config_only()`, `remove_config_only()`
* support for required config-only args
* inclusion in help message
* checks for collisions between regular dests and config-only args
* `MagiConfigError` exception class
* `write_config()` can specify default obj name
* `remove_argument()` function added
* `ArgumentDefaultsRawHelpFormatter` convenience class (imported from ConfigArgParse)
* README rewritten and improved
* Slight improvements in examples

* optional command-line arguments in config settings to toggle strictness: `strict_args`, `strict_help`
* allow changing config options after initialization: `set_config_options()`
* support positional config args
* fix help and usage messages (result of significant behind-the-scenes improvements)
* configurable dests for config parameters: `dest`, `obj_dest`, `strict_dest`

Add new feature `obj_arg`, custom help messages for config and obj arguments, and a new example.

Another fix for PyPI.

Fix a typo in README.md and fix PyPI distribution.