Replaced comparison-based sort with key based sort in BaseContext.unify_types() (fixes 2/3 compatibility issues).
Replaced comparison-based sort with key based sort in BaseContext.unify_types() (fixes 2/3 compatibility issues).

GaZ3ll3/numba,IntelLabs/numba,gdementen/numba,IntelLabs/numba,numba/numba,IntelLabs/numba,numba/numba,GaZ3ll3/numba,gdementen/numba,pombredanne/numba,sklam/numba,jriehl/numba,gdementen/numba,sklam/numba,pitrou/numba,pitrou/numba,numba/numba,pitrou/numba,cpcloud/numba,gmarkall/numba,numba/numba,stuartarchibald/numba,sklam/numba,numba/numba,seibert/numba,cpcloud/numba,pombredanne/numba,seibert/numba,seibert/numba,gdementen/numba,ssarangi/numba,ssarangi/numba,stonebig/numba,sklam/numba,gmarkall/numba,ssarangi/numba,pombredanne/numba,GaZ3ll3/numba,cpcloud/numba,pitrou/numba,jriehl/numba,stuartarchibald/numba,cpcloud/numba,seibert/numba,stefanseefeld/numba,IntelLabs/numba,stonebig/numba,jriehl/numba,gmarkall/numba,cpcloud/numba,IntelLabs/numba,gmarkall/numba,gdementen/numba,seibert/numba,stonebig/numba,ssarangi/numba,jriehl/numba,gmarkall/numba,pitrou/numba,ssarangi/numba,stonebig/numba,stuartarchibald/numba,stefanseefeld/numba,GaZ3ll3/numba,pombredanne/numba,GaZ3ll3/numba,jriehl/numba,stefanseefeld/numba,pombredanne/numba,stuartarchibald/numba,stefanseefeld/numba,stonebig/numba,stuartarchibald/numba,stefanseefeld/numba,sklam/numba