Cleaning up text handling in the accessibility merge
Initial accessibility element outlining
Checkpointing accesibility frame work
Reworking the accessibility frame calculation

This uses CTLineGetBoundsWithOptions and CTRunGetTypographicBounds
instead of relying on the slower CTRunGetImageBounds calculations.
The rectangle also seems to be tighter.
Initial accessibility element combining

This is an improvement for the speech to text engine because while
some span elements indicate stress or special treatment of the text
visually, having the text read out and stopping for each one is
awkward.
Corrrecting for applicable ranges in accessibility frame calculation