Incorporate useful bits of nipype1topydratask

[effigies]

@dPys and @anibalsolon have worked on this: https://github.com/dPys/nipype1topydratask/blob/master/converter.py

[dPys]

I wonder how this might be expanded upon to automate detection of nipype1 objects that need conversion? Maybe take inspiration from the fixer classes of other conversion tools (e.g. the infamous 2to3?) https://github.com/maxking/cpython-1/blob/master/Lib/lib2to3/fixer_base.py