First cut at bdist_pex

[msabramo]

Something to start with

$ pwd
/Users/marca/dev/git-repos/pex

$ python -V
Python 2.7.9

$ python setup.py bdist_pex
running bdist_pex
creating dist/pex-1.0.0.dev3.pex

$ dist/pex-1.0.0.dev3.pex
Python 2.7.9 (v2.7.9:648dcafa7e5f, Dec 10 2014, 10:10:46)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>

$ python setup.py bdist_pex --python=python3.4
running bdist_pex
creating dist/pex-1.0.0.dev3.pex

$ dist/pex-1.0.0.dev3.pex
Python 3.4.2 (v3.4.2:ab2c023a9432, Oct  5 2014, 20:42:22)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>

$ python setup.py bdist_pex --python=python3.4 --dist-dir=pex-dist
running bdist_pex
creating pex-dist/pex-1.0.0.dev3.pex

$ pex-dist/pex-1.0.0.dev3.pex
Python 3.4.2 (v3.4.2:ab2c023a9432, Oct  5 2014, 20:42:22)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>>

See #99.

Cc: @sontek

[msabramo]

Note that @wickman has his own branch where he's been working on this -- see master...wickman:wickman/99 and I've sent some PRs to his branch: https://github.com/wickman/pex/pulls/msabramo

[wickman]

This is now merged as part of 1d1cae2