Allow use of hacking 0.6.0 and fix min version

Change-Id: Iaf75b8991c6a7c79a22651ca15867adda4dac2b1
Fix python 3.3 test configuration

It is no longer necessary to install testrepository from bzr,
so don't. That means we no longer need a separate py33
environment definition, or the special requirements file.

Do not use distribute in the test virtualenvs.

Change-Id: I1c0002d3992e25e7e0927eca85ccd5e4d57ee7d1
Merge "Allow use of hacking 0.6.0 and fix min version"