t_PADIC to t_INTMOD and use of chinese()

dueHello,

I have a couple of requests:

1) An easy way to convert t_PADIC to t_INTMOD, maybe extending Mod() to
support a single argument of type t_PADIC, e.g. Mod(1 + O(5^2)) would
produce Mod(1, 25).

2) Extend chinese() to support t_PADIC arguments (still producing t_INTMOD).

Thanks,
Max