Coerce `dtype` to `numpy.dtype`
Coerce `dtype` to `numpy.dtype`

This should allow other inputs to `dtype` like strings with the type in
them. Also will raise a clearer error message if the user provides
something that cannot be converted to a `numpy.dtype`.

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