Fixed:
- Undo added to stack when no changes made with cut, paste, delete
- Using generator with `set_column_widths()`/`set_row_heights()` would result in lost first width/height
- Header/Index dropdown `modified_function` not sending modified event
- Escape out of dropdown box doesn't reset arrow orientation
Added:
- Cell formatters, thanks to [PR158](https://github.com/ragardner/tksheet/pull/158)
- `format_cell()`, `format_row()`, `format_column()`, `format_sheet()`
- Options for changing output to clipboard delimiter, quotechar, lineterminator and option for setting paste delimiter detection
- Bindings `"up" "down" "left" "right" "prior" "next"` to enable arrowkey bindings individually use with `enable_bindings()`/`disable_bindings()`
= Dropdowns now have a search feature which searches their values after the entry box is modified (if dropdown is state `normal`)
- Dropdown kwargs `search_function`, `validate_input` and `text`
Removed:
- Startup arg `ctrl_keys_over_dropdowns_enabled`, also removed in `set_options()`
- `set_copy` arg in `set_cell_data()`
- `return_copy` arg in data getting functions but will not generate error if used as keyword arg
Changed:
- `index_border_fg` and `header_border_fg` no longer work, they now use the relevant grid foreground options
- `"dark"`/`"black"` themes
- Dropdowns now default to state `"normal"` and validate input by default
- `set_dropdown_values()`/`set_index_dropdown_values()`/`set_header_dropdown_values()` keyword argument `displayed` changed to `set_value` for clarity
- Checkbox click extra binding and edit cell extra binding (when associated with a checkbox click) return `bool` now, not `str`
- `get_cell_data()`/`get_row_data()`/`get_column_data()` have had an overhaul and have different keyword arguments, see documentation for more information. They also now return empty string/s if index is out of bounds (instead of `None`s)
- Rename some internal functions for consistency
- Extra bindings delete key now returns dict instead of list for boxes