Create a c302 DataTranslator and DataSources

[mwatts15]

PyOpenWorm has a notion of DataTranslators that describe how data get from
one form to another and each of those forms is called a DataSource. A
DataSource should be created to describe the input to c302 and a DataSource
should be created to describe the output NeuroML files. The DataTranslator
should have a translate method which runs c302 with the first DataSource
type and outputs the second. The first DataSource should have a Translation
linking it back to the PyOpenWorm insert_worm DataSource (TBD:
openworm/owmeta#364).

blocked by openworm/owmeta#364