* include/experimental/numeric (gcd): Reject cv-qualified bool.
(lcm): Likewise.
* include/std/numeric (gcd): Likewise.
(lcm): Likewise.
* testsuite/26_numerics/gcd/gcd_neg.cc: Add tests and adjust.
* testsuite/26_numerics/lcm/lcm_neg.cc: Likewise.

From-SVN: r254736