Allow Option to Delete Whole Word when Gestured Typed or Backspace Long Press

[Astronox]

I think the title is self explanatory. If I gesture type a word and it's wrong, often it's completely wrong. I think it would be useful to allow an option to delete a whole word if it was gesture typed.

I think it could be implemented in one of two ways:
-Add a checkbox to the Gesture Typing options page for "backspace deletes whole gesture typed word".
or
-Under "Tweaks and More" add a checkbox for "hold backspace to delete whole word".

I think both of these would be good additions, but either would give a solution to the problem of mistyped gesture words.
The second suggestion was already suggested here: #3646