Update CHANGES.rst to reflect new changes.
Update CHANGES.rst to reflect new changes.

jsirois/pex,kwlzn/pex,pombredanne/pex,mzdanieltest/pex,URXtech/pex,rouge8/pex,pantsbuild/pex,jamesbroadhead/pex,sixninetynine/pex,rouge8/pex,snyaggarwal/pex,jsirois/pex,pantsbuild/pex,kwlzn/pex,URXtech/pex,pombredanne/pex,jamesbroadhead/pex,sixninetynine/pex,snyaggarwal/pex,mzdanieltest/pex