[#1859] Clean pyc files, speed up directory delete operation, fix Windows newlines conversion.

Problem description
===================

paver clean was not removing pyc files, so when switching between python2.7 and 2.5 we had a lot of nasty errors.


Changes description
===================

clean was changed to delete pyc files.

As a side fix, I have also tried to speed up clean operation on windows as it was ridiculous slow. 3min on Windows vs 1 second on Linux. 

As another  side fix, I have fixed the rendering of RST files, as this was a blocker for release a maintenance release for 1.8.

As another side fix I have improved the binary dist process by getting Python packages from a single place.

We manually download pip and setuptools Python package since we need pip/setutools in order to get the packages from PyPi. But pip and setuptools are real Python packages witch can be published on PyPi.

I have also fixed the conversion of newlines to windows standard.


How to try and test the changes
===============================

reviewers @alibotean @dumol 

check that clean works on your system and on all OS:
```
paver test_remote all --properties=force_clean=yes
```

Check that changes make sense.

Thanks!