use 4.3 latest for test buildout
add a test that exposes the issue reported in https://dev.plone.org/ticket/15306
register an adapter for the FileUpload field moved from Products.CMFDefault

fixes https://dev.plone.org/ticket/15306
Merge pull request #25 from plone/fix-15306

Fix missing adapter for portrait field in registration forms

Hope you all don't mind self-merged PRs.  If so, I apologize and will revert.