0.3.0g1

Adds support for 3 new pex_binary parameters:

  req_files: Add requirements from the given requirements files. Must be provided as labels.

    This feature will reduce build determinism!  It tells pex to resolve all
    the transitive python dependencies and fetch them from pypi.

    It is recommended that you use `eggs` or specify `no_index` instead where possible.

  no_index: Whether to use pypi to resolve dependencies for `reqs` and `req_files`; Default: False

  repos: Additional repository labels (filegroups of wheel/egg files) to look for requirements.