add experts index entries for deepfreeze, frozen modules and subinterpreters

[kumaraditya303]

No description provided.

[hugovk]

Thank you!

If you like, you can add an asterisk after your name, but it's completely optional:

Unless a name is followed by a ‘*’, you should never assign an issue to that person. Names followed by a ‘*’ may be assigned issues involving the module or topic.

[kumaraditya303]

If you like, you can add an asterisk after your name, but it's completely optional

Yeah I read that but I usually assign issues to myself after I read through the bug report so I'll not add asterisk.

[gvanrossum]

I don't think that voidspace (Michael Foord) is active any more. I'll ask him.