Add pitch as an option for capitalization presentation

As reported by Joanmarie:
“set_cap_let_recogn() lets one choose amongst:
* none
* spell
* icon

Orca has always provided this via pitch. I've implemented support in Orca for the above and would love to see pitch being something I could set via the same API rather than it being entirely separate.

Please and thank you. :)”

Start at the set_cap_let_recogn() API mentioned in the issue and trace how its capitalization presentation options are defined and applied. Compare the existing none, spell, and icon choices with Orca's pitch behavior; done means pitch can be selected through the same API and the existing choices continue to work.

Written by the indexing model from the issue text.