[#1838] Self contained repository.

Problem description
===================

This add support for having independent repository, ie they will no longer depend on brink repo.

This is just the initial branch for brink and aver.sh script.

Once it looks good, I will create separate tickets for applying the changes in all other repositories.


Changes description
===================

instead of using brink/cache the cached files will be downloaded in REPO/cache folder.

I first tried to put them in REPO/build-*/cache ... but then the cache would be removed at each clean operation and a huge new download will be required.

With this change you should be able to place the repository in any folder structure.

With this changes, the setup.py publish target was updated to no longer force the local general cache from brink/cache since  we no longer use it.

The diff is huge since I have removed a lot of code that become unused after this change. The main diff is in a single commit.


How to try and test the changes
===============================

reviewers @alibotean @dumol 

Check that changes make sense.

Get the new brink repository in a random location.

Use paver.sh from the new repository to run the tests.

Thanks!