Change TransportData __repr__ function and fix pdep/network#_#.py files.

@enochd pointed out in a comment to commit 
8a6d32441007649807e3137ba7da0e6c2dab9f6d
that RMG-py was creating cantherm/measure input files
(eg. pdep/network23_1.py) that were malformed.

This should fix it, I hope.