3. verylong: exploit pi-AGM book routines, look at Joerg Arndt's algorithms.
6. move sources to subdirectories
7. add combinatorial, linear algebra, factorization, polynomial functions
   as in SAC-2.
7. add modular integers vectors/polynomials implemented as bit/byte vectors.
7. chinese remainder algorithm, maybe Hensel-lifting as in Magnum.
8. factor and primality testing for small integers
8. primality test in Z:
   + polynomials cl_UP, cl_UP_I, cl_UP_MI, cl_MUP_MI, cl_MUP_I, cl_UP_C, cl_UP_R
     with operator() for evaluation
   + - small prime table
     - Pollard rho
     - Rabin-Miller 8.2.2
   + Cornacchia 1.5.3
   + - exp
     - complex values of j()
     - Hilbert polynomial for j() 7.6.1
   + roots of polynomials mod N 1.6.1
   + Jacobi/Legendre symbol
   + - elliptic curves, Jacobi representation
     - m.P on elliptic curve
   + Atkin's algorithm
9. modsqrt (Tonelli/Shanks for small e, Cantor-Zassenhaus for big e).

Document the timing class

