[Distutils] Building wheels for dependencies with distlib, wheeler.py and vanilla pip.

[Vinay Sajip]

I've updated the wheeler.py script [1] to build wheels for dependencies by
default, though you can turn that off by specifying --no-deps. It's smart about
not repeating work if dependencies are common across multiple distributions you
specify:

    $ python wheeler.py pygments flask
    Finding the dependencies of pygments ...
    Finding the dependencies of flask ...
    Pipping Werkzeug==0.8.3 ...
    Pipping Jinja2==2.6 ...
    Pipping Pygments==1.6 ...
    Pipping Flask==0.9 ...
    The following wheels were built:
      Werkzeug-0.8.3-py27-none-any.whl
      Jinja2-2.6-py27-none-any.whl
      Pygments-1.6-py27-none-any.whl
      Flask-0.9-py27-none-any.whl

It seems to work for Pyramid, too (Marcus asked about it), though there are
some 2.x/3.x issues relating to Unicode, zip file entries and csv files that
I'm investigating (Pyramid has some test fixture files with Unicode filenames).

You should pull the latest changes from distlib before using wheeler.py, as I
fixed some errors in Unicode handling.

Regards,

Vinay Sajip

[1] https://gist.github.com/vsajip/4988471