Flicker

1. Upgraded use of pandas to remove warnings about deprecated pandas API
2. Added some docstrings
3. Added more checks in some functions along with new tests
4. Tested on Python 3.13
5. Added `flicker.concat` function to concatenate multiple dataframes at once
6. Added `flicker.FlickerDataFrame.schema` and `flicker.FlickerDataFrame.from_schema` to easily create empty dataframes with the correct schema

**Full Changelog**: https://github.com/ankur-gupta/flicker/compare/1.1.0...1.2.0

Added tab-completion of column names via the [`_ipython_key_completions_` method](https://ipython.readthedocs.io/en/stable/config/integrating.html).

Releasing [version 1.0.0](https://github.com/ankur-gupta/flicker/releases/1.0.0) containing breaking changes.
1. `flicker.FlickerDataFrame` is rewritten to remove unnecessary alias methods
2. `flicker.FlickerColumn` has been added which provides a lot of functionality without verbosity
3. `flicker` now works more recent Python 3.9+ and PySpark 3.4.1+.
4. Test coverage has been increased to [99%](https://app.codecov.io/gh/ankur-gupta/flicker).

* Changed columns argument to names because we need to distinguish between a Column object and the column name
* Documentation (still WIP) is now available at https://flicker.perfectlyrandom.org/

* `df.group()` now returns `FlickerGroupedData` object instead of `pyspark.sql.GroupedData` object
* `df.group().count()` will now return a `FlickerDataFrame` object instead of a `pyspark.sql.DataFrame` object