Request for new functions...

[Torbjorn Granlund]

We're considering some support of wider-than-long types,
but there are several things that make this tricky.

I don't like forcing "mp_limb_t" onto users, since as an abstract type
users will not know how to handle it, such as how it relates to standard
types, how to print it, etc.

Then that leaves long long, which is in the C99 standard, which we have
not yet decided to require. 

I have a partial implementation of such a thing, though.  Not just
function prototypes, but real code.  :-)  I will finish and integrate
it when time is ripe.

-- 
Torbjörn