Tabulous

What's Changed
* Fixes for Qt6 by hanjinliu in https://github.com/hanjinliu/tabulous/pull/131
* Restrict the length of tooltip by hanjinliu in https://github.com/hanjinliu/tabulous/pull/132
* Replace nan value to "" in spreadsheet by hanjinliu in https://github.com/hanjinliu/tabulous/pull/133


**Full Changelog**: https://github.com/hanjinliu/tabulous/compare/v0.5.6...v0.5.7

Bug Fixes
----------
- Do not save index if it is not edited.
- Do not copy the name of column header.
- Fix double-click event of matplotlib figures.
- Fix the preview matplotlib figure tick colors when the viewer theme is dark.
- Fix the opacity of highlight color.

New Features
------------------
- Tabs can be deleted by right drag.
- Implement table column proxy (125).
- Use dynamic scrollbar for spreadsheet (130).
- Use `N` in cells for the number of rows.

Bug Fixes
----------
- Fix in-cell slots (126).
- Fix sort button behavior (127).
- Fix segfalut in test (128).
- Fix plot UI.

Improvements
----------------
- Asynchronously import `qtconsole`, `matplotlib` and `scipy` to boost startup.
- Implement `append` method to `Table` and `SpreadSheet`.
- Show viewer after some function calls.
- Improve dark-theme syntax style of QtConsole.

Deprecations
--------------
- Methods and menus that add cell widgets are all deprecated since its behavior is not compatible with row/column insertion/deletion.

Bug Fixes
----------
- Fix switch headers.
- Fix pasting from numpy-style text.
- Fix Japanese and Chinese preedit text.

Improvements
---------------
- Implement custom IPython auto completion (121).
- Add custom ipython magics (122).
- Add jump-to-cell widget and assign Ctrl+G to it (123).
- Implement animation (124).

Changes
---------
- Add pyproject.toml and github workflow.

Bug Fixes
----------
- Fix file explorer.
- Fix bugs in Qt6 (key sequences).
- Fix s `runpy` bug on startup.
- Fix close confirmation not being shown.
- Fix the traceback dialog when it encountered an exception with no argument.
- Fix the architecture of row/column spans.

Changes
----------
- Use latest `qt-command-palette` (116).
- Add distributions from `scipy.stats` (117).

Bug fixes
----------
- Consider HTML escape sequences in the traceback dialog (118).
- Fix `assign` function (119).
- Don't update cell values if escaped by `Esc`.
- Match color for each theme (120).