Avoid unwilling testing negative zeros in test_ufuncs
Avoid unwilling testing negative zeros in test_ufuncs

This and a rint() bug on win32 were the cause of the Jenkins failures.

IntelLabs/numba,stefanseefeld/numba,stefanseefeld/numba,stuartarchibald/numba,gmarkall/numba,numba/numba,numba/numba,IntelLabs/numba,IntelLabs/numba,jriehl/numba,sklam/numba,stefanseefeld/numba,seibert/numba,gmarkall/numba,cpcloud/numba,jriehl/numba,jriehl/numba,stuartarchibald/numba,cpcloud/numba,stonebig/numba,numba/numba,cpcloud/numba,sklam/numba,numba/numba,seibert/numba,gmarkall/numba,cpcloud/numba,numba/numba,gmarkall/numba,IntelLabs/numba,stonebig/numba,seibert/numba,stuartarchibald/numba,seibert/numba,stonebig/numba,stuartarchibald/numba,sklam/numba,jriehl/numba,stonebig/numba,seibert/numba,cpcloud/numba,jriehl/numba,sklam/numba,stuartarchibald/numba,stonebig/numba,gmarkall/numba,IntelLabs/numba,stefanseefeld/numba,stefanseefeld/numba,sklam/numba