ctn-waterloo/nengo — pull request #298 by arvoelke (2014-03-27 17:39:21+00:00)
Title: Maintain hierarchy in api, enforce with (Rebased)

Cherry-picked dd63c9bb5e4dddd4d07a469bd4076aba8b08ee70.
- Model is recursively structured.
- `with` is required.
- Fixed a test which occassionally failed due to floating point
comparisons
- `NengoObject` base class for simplifying `__hash__`, `__str__`, etc...
- A bit of general cleanup with string quotes and specifiers