Is your feature request related to a problem? Please describe.

1. I would like to have sayAll to read table column/row.
2. I would like to have a way to read the first cell in current column/row without moving the cursor.

Describe the solution you'd like

I propose to implement 4 table-related keystrokes:

• NVDA+Control+Alt+RightArrow/DownArrow: reads cells in current row/column starting from the current cell. Will stop reading once reaches the end of table. Will move caret as it reads every next cell.
• NVDA+Control+Alt+LeftArrow/UpArrow: reads cells in current row/column starting from beginning. Will stop reading once reaches the end of table. Will NOT move caret, so this can be used to learn heading of current column/row.
  These commands are already implemented in Tony's enhancements add-on (although with different default key bindings) - as a proof of concept.

Describe alternatives you've considered

I am only aware of SayAll command (NVDA+DownArrow) that is similar to my proposed NVDA+Control+Alt+RightArrow command to read current row starting from current cell. However the default SayAll will not stop at the end of the row, so it is less convenient.
I am not aware of sayAll for current column, nor any good solution of figuring out heading of current cell/current row in stock NVDA.

Additional context

Will be happy to implement this PR myself if no objections.