[chef] ffi-yajl 1.4.0 release

[Lamont Granquist < >]

This is just a minor release which went out a few minutes ago which 
clears up an error message when utf8 validation fails, along with 
correctly exposing the switch to be able to turn off utf8 validation in 
the libyajl c library.  Also better detection of windows platform 
(mostly cygwin fix).