[Enhancement] Add row- and column-wise editing

[sbliven]

I would love to see some commands in table mode to rearrange rows/columns.

• Move a whole row up/down or a column left/right
• Yank a column and paste elsewhere
• Insert (#130, #119) and delete rows/columns

[dhruvasagar]

@sbliven At the time of this writing we already have the ability to delete rows / columns and insert columns. I think it should be valuable to introduce text objects that represent a row / column and that should enable us to build extensions for the requested features.

[sbliven]

Nice! This makes column manipulation possible. It might still be nice to have single commands for some of these to speed up the workflow.

Some sequences:

• Move row: delete line dd or\tdd; move to new location; yank yy
• Move column: insert a new column \tic; select old column in block visual mode C-V and yank y; paste in empty column p; delete old column \tdc

As an aside, I prefer \tac and \tic for inserting columns after and before the current cursor, for consistency with a and i.