refactor cryptol server methods for saw server

[pnwamk]

In 4b452cb we duplicated some code (here, here, and here) to make merging all the submodule updates smooth.

Now, however, need to remove this duplication by exposing the duplicated, more polymorphic versions of those functions as illustrated by this cryptol diff and this saw-script diff (modulo any additional changes needed based on other repo activity of course).

[RyanGlScott]

I think this was done in #1109, correct?

[pnwamk]

Yes, thanks for the reminder =)