Add precise() to numeric_traits

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
Add missing library, the interval library contains the explicit instantiation of interval<mpq> and interval<double>

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
Add power operator to mpq

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
Add power operator to numeric_traits

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>