Consider using concurrent.futures in place of smqtk.utils.parallel

[danlamanna]

For Python >=2.6, <3 the backport of futures can be used, otherwise the built in support for Python >=3.2 can be used.

[Purg]

In a lot of cases I agree with this. There is still a possible niche application of the smqtk.utils.parallel.parallel_map in that it can parallelize the execution of on-the-fly functions and lambda expressions. I grant that this is less common.