* Created public subroutine to compute enhanced diffusivity (one last comparison to make with POP's KPP routine)

* Introduced round-off level change in test 4 of the KPP stand-alone routine by changing how zw is computed in cvmix_kpp_drv (no effect on actual KPP routine used by GCMs)

* Fixed minor bug in Bryan-Lewis implementation: compute atan(b3*(-zw - b4)) rather than atan(b3*(|zw| - b4)) [only a problem when zw>0, implying interface above sea level]

* Updated NCL script for KPP plot to ensure depth-axis is labeled with negative values and it's easy to switch between postscript, PDF, and X11 output.

* Updated protex documentation to include compute_enhanced_diff description.



git-svn-id: https://cvmix.googlecode.com/svn/trunk@278 ec264166-b127-864d-6cb2-e100125a5c76