Work around STP wide bitvector construction issues.
Work around STP wide bitvector construction issues.

STP refuses to construct bitvectors wider than an unsigned long long
from an unsigned int, so construct them from a string instead. They both
only need to be zero anyway.

Monotone-Parent: 8564b973a044c90d3af39d9cb7970493887ae0ba
Monotone-Revision: c5b8a6a815f3a01799b96f5602fb6ddb4e8ebca3

FrancisRussell/fnv_solver