Rewrite Table section

[knstvk]

Environment

• Documentation version: 7.2
• Part of the documentation: Manual
• Existing page: https://doc.cuba-platform.com/manual-7.2/gui_Table.html

Description of the bug or enhancement

Add "Working with ..." or "Usage of ..." subsections similar to the DataGrid description:

• "Working with generated columns" - describe various ways of defining generated columns starting from using handlers tab in Studio
• "Formatting values"
• "Working with aggregated values"
• "Providing icons and styles"
• etc.

See also #474