TypewriterPosition<T>
TYPE DEFINITION
When you loop over a Typewriter, using a `for-of` statement, you
iterate over all positions in the Typewriters text. These positions
are represented by a `TypewriterPosition`.
`TypewriterPosition` contains the character for that position,
the position (index) of that character, and all cursors currently
on the position. Lastly it will contain all cursors that have
selected the position.
Since 1.2.0