Make the Python generator dynamic.

- Modify the Python generator constructor to fit the new generic interface.
- Register the Python genrator with the central registry.
- Deprecate the old way of invoking the Python generator.
- main.cc no longer includes t_py_generator.h.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665612 13f79535-47bb-0310-9956-ffa450edef68
3 files changed