Add NumPy version guard.
Add NumPy version guard.

As title.

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