Working on linear algebra interface
Added aring-zz-gmp file (ARingZZGMP).  Replaced CoefficientRingZZ_NTL

with this class.  Testing is still required.
Added newpromote function.  Will eventually replace all uses of promote.

(And will be named promote).
Added ARingQQFlint type

It is currently linked by QQ, meaning that this commit will not compile
without flint.