TypewriterCursorSelection
TYPE DEFINITION
Represents the selection of a cursor. A selection has a `start`
and and `end` which are both numbers representing two positions
within a `Typewriter`'s `text` property.
The `start` will always lie before the `end`.
The `position` of a cursors is always either on the `start` or
`end` of the `selection`.
Since 1.2.0