Add functionality to restart NVDA when adding and copying voices as an add-on

[ericdq]

I recently installed IBMTTS on a clean version of NVDA, as the previous one was giving me strange errors.

I would like when importing the library of voices and when copying them as an add-on the added functionality for NVDA to restart.
Currently it appears in a message that the add-in voice will be used after NVDA restarts.
It has generated some errors for me not reading this message carefully. I also don't know what could happen if a portable copy is made immediately after accepting the message but without restarting NVDA.