`update-versions-file = true` has no effect when `show-picked-versions` is
false.

Prep for release.

Provoke a travis-ci run. :)

Fix for #64: __pycache__ dir inside distutils scripts metadata directory

Reinout distutils script encoding fix for #65

Should never ever happen, of course, but somewhere in the universe exists a
distutils script with just the `#!bin/python` line... Added a len() to guard
against that.

Added a note as suggested by Marius

The second line is now inspected for a source encoding

I used Marius' suggestion (with one additional fix). The issue is demonstrated
by the test in @77cd8b16. This commit fixes
the failing test.

Fixes #64

A directory hacked inside the distutils `EGG-INFO/scripts` metadata directory
(which can apparently happen in python 3.3 with a `__pycache__` directory)
breaks the current distutils script detection code.

Refs #64

Fixed filename of distutils-scripts on windows. Fixes #52

Adding missing *.test files to manifest, needed for manuel tests

Merging buildout-versions' functionality into buildout

Unlike the console-script entrypoint scripts, the distutils
scripts didn't get a -script.py appended to their name on
windows. This is now fixed.

As discussed on the mailinglist: better to have python version checking
as a separate buildout option instead of hidden in the [versions] part.
And... the python version checking itself needs to be more robust.
sys.version is too long, minor/major needs explicit checking.

Drop trove classifiers for Python 2.4 and 2.5

I guess this was why the pull request wasn't build.

An 'update-versions-file' option points at a file you want updated.

I cannot handily use print_ from buildout.py as I get a circular import that way.