Thrift: Pre-generate reflection_limited for Python.

Thrift: Pre-generate reflection_limited for Python.

Summary:
- Give reflection_limited a nice clean Python module.
- if/regen.sh now generates reflection_limited for Python and copies it to src.
- Added the generated Python for reflection_limited to version control.
- lib/py/setup.py installs reflection_limited.
- lib/py/cleanup.sh now removes build (make sure to run as root).
- The C++ version of reflection_limited was also updated by regen.sh.

Reviewed By: mcslee

Test Plan:
- Clean build and install.
- Look at the installed Python files.
- python -c 'from thrift.reflection.limited.ttypes import *'

Revert Plan: ok

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665235 13f79535-47bb-0310-9956-ffa450edef68