Curate demos, examples and tutorials

[corranwebster]

There is a lot of material in the examples directory, however it is not well organized and the point of may examples is not clearly explained. Some effort should be spent to curate the examples, removing duplicates, modernizing code, and improving explanations.

[kitchoi]

This example made my computer hang to the point I had to restart: examples/demo/Advanced/Table_editor_with_live_search_and_cell_editor.py

The reason why that happened to me was because I happened to run it from a directory that also contains a handful of Python virtual environments. This demo tries to index everything in the current directory, recursively. Therefore it spent an awful lots of time and memory trying to index my directory. The example was probably written assuming the current directory was the example folder. For demonstration purposes, we probably want to ensure the default folder contains a limited amount of data files.

[ievacerny]

So far all demos in examples/demo/Standard_Editors have been fixed up and warnings about broken demos added where relevant.

A list of demos that have been fixed up in examples/demo/Advanced:

• Auto_update_TabularEditor_demo.py
• Date_editor_demo.py
• Date_range_editor_demo.py
• List_editors_demo.py
• Multi_select_string_list.py
• NumPy_array_tabular_editor_demo.py
• Property_List_demo.py
• String_list_ui_editor.py
• Table_editor_with_checkbox_column.py
• Table_editor_with_context_menu_demo.py
• Table_editor_with_progress_column.py
• Tabular_editor_demo.py
• Tabular_editor_with_context_menu_demo.py
• Time_editor_demo.py

I briefly looked at examples/demo/Advanced/Auto_editable_readonly_table_cells.py and I think this demo is not worth fixing up - the functionality doesn't seem to exist in Qt implementation and Wx implementation is broken with multiple different errors. It might be best to just delete it.