[#2228] Update paver to latest build system

Problem
-----------

paver does not work on python-packages

Why
-----

It uses an old version which does not support self contained repos.

Changes
-----------

Update paver.

I did a test run and things look ok http://build.chevah.com/builders/python-package-ubuntu-1204/builds/6

How to test
---------------

reviewers: @dumol 

```
paver deps
paver test_remote aix-53
```