Dfvue

* Larger entry fields for Windows.
* Add xlim, ylim, and y2lim options.
* Increased number of digits in format_coord_scatter.
* Use ncvue theme with customtkinter.
* Removed addition of index to column names when sorting variable
names.
* Keep NaN values as str when reading csv.
* Bugfix when no file given on command line.
* Possibility to pass `pandas.DataFrame` directly to dfvue in
Python.
* Bugfix when checking if csvfile was given.
* Add low_memory to read_csv switches.

* Make standalone packages.
* Sync `ncvwidgets` with developments in `ncvue`.

* Back to pack layout manager for resizing of plotting window.
* pyplot was not imported on Windows in `dfvue`.
* `Transform` window to manipulate DataFrame.
* Correct datetime formatting in coordinate printing.
* Move from token to trusted publisher on PyPI.
* Silence FutureWarning from `pandas.read_csv`.

* Allow multiple input files that will be concatenated.

* Use Azure theme if CustomTkinter is not installed such as in
conda environments.
* Increased size of ReadCSV window to fit widgets on Windows.

* Exclusively use CustomTkinter.
* Updated documentation with new screenshots.