Add test for gpu datetime
Add test for gpu datetime

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