allow loop and time limits in BKZ
Trac #16798: fpLLL API misuse

Sage currently raises a runtime error whenever fpLLL returns a nonzero
return value. However, nonzero return values are expected under some
conditions (when the time or the number of loops is restricted).

URL: http://trac.sagemath.org/16798
Reported by: malb
Ticket author(s): Martin Albrecht
Reviewer(s): Martin Raum