require cffi >= 1.4.1
require cffi >= 1.4.1

Previous versions of cffi didn't know about common
types or any of the Windows types when using an out-of-line
module.  Version 1.4.0 if cffi should fix contain a fix however:

  https://bitbucket.org/cffi/cffi/issues/228/bool-type-as-callback-argument-not-working

Rather than requiring 1.4.0+ we're using 1.4.1+ because of another issue:

  https://cffi.readthedocs.org/en/latest/whatsnew.html#v1-4-1

opalmer/pywincffi,opalmer/pywincffi,opalmer/pywincffi,opalmer/pywincffi