Add two vmaps that call ExpandVisualSelection() for the appropriate
direction.
That expands the selection over all directly following lines in the
given direction that contain the current selection at the same position.
Example:
```
- TODO: ...
- TODO: ...
- TODO: ...
```
In visual block one can select `TODO: ` on the first line and then call
`ExpandVisualSelection(1)` which results in a block selection that spans
over all other TODOs as well.
Julian Prein
44194bd09c
