Add support for Pecan *without* thread local request/response objects

Change-Id: I5a5a05e1f57ef2d8ad64e925c7ffa6907b914273
Test ceilometer on py27.

Change-Id: I885dbfbddd2d6acdcbec6271acbccaebbc0de5de
Merge "Add support for Pecan *without* thread local request/response objects"