Added subsystem_apply.py, which includes more efficient algorithms for the application of CPTP maps to individual components of composite quantum systems. Added super_to_choi.py, which contains a few utility functions for converting between different representations of CPTP maps. This is the first commit, likely much to do to improve efficiency, but basic functionality has been ensured.
Attempted PEP 8 compliance, n
Fixing accidental overwrite of super_to_choi.py caused by autopep8
Attempting to resolve conflict
More pep8-related conflicts
More pep8-related conflicts
Interim commit, writing unit tests
Changes according to message from jrjohansson May 28
Merge pull request #22 from bcriger/master

Efficient Application of CPTP Maps to Subsystems