Added cases:
Analyse auto indention for new lines. It mean, that redo/undo
line creation will finished by one step.
Analyse input symbols speed. In case when user writes somethenigi
and takes a short delay (by default 0.8sec)
between written symbols - redo/undo action will use this delay
as point to create new node in redo/undo queue.
Analyse input symbols on a "words". Ongoing alphabetic symbols
between nonalphabetic symbols known as
"word". Redo/undo action will use for a step a whole "word".
In text setting added addition toggle named "Smart undo/redo".
By default this feature is disabled.
Todo: make this feature work with auto intendation.
Prortotype here: https://phab.enlightenment.org/D1288