BUG: Export ITK_FFTW_INCLUDE_PATH as CMake path.
BUG: Export ITK_FFTW_INCLUDE_PATH as CMake path.

In FindFFTW.cmake, the FFTW_INCLUDE_PATH is converted to a CMake Path, i.e.
separated by unix /. This corrects that value of ITK_FFTW_INCLUDE_PATH on
Windows so the backslashes are not treated as escapes when that file is read
in.

Change-Id: I82d0297aa7d4d044db34437c32ff71147b425871

malaterre/ITK,jmerkow/ITK,PlutoniumHeart/ITK,LucHermitte/ITK,BlueBrain/ITK,Kitware/ITK,jcfr/ITK,zachary-williamson/ITK,ajjl/ITK,vfonov/ITK,LucasGandel/ITK,jmerkow/ITK,fbudin69500/ITK,malaterre/ITK,thewtex/ITK,jcfr/ITK,jmerkow/ITK,atsnyder/ITK,malaterre/ITK,biotrump/ITK,InsightSoftwareConsortium/ITK,jmerkow/ITK,zachary-williamson/ITK,LucasGandel/ITK,vfonov/ITK,zachary-williamson/ITK,thewtex/ITK,biotrump/ITK,spinicist/ITK,Kitware/ITK,richardbeare/ITK,hjmjohnson/ITK,stnava/ITK,BRAINSia/ITK,richardbeare/ITK,biotrump/ITK,hjmjohnson/ITK,vfonov/ITK,BlueBrain/ITK,fbudin69500/ITK,richardbeare/ITK,malaterre/ITK,Kitware/ITK,jmerkow/ITK,blowekamp/ITK,atsnyder/ITK,atsnyder/ITK,LucHermitte/ITK,blowekamp/ITK,fedral/ITK,thewtex/ITK,ajjl/ITK,vfonov/ITK,jcfr/ITK,msmolens/ITK,ajjl/ITK,ajjl/ITK,spinicist/ITK,malaterre/ITK,hjmjohnson/ITK,LucHermitte/ITK,BRAINSia/ITK,ajjl/ITK,PlutoniumHeart/ITK,jmerkow/ITK,blowekamp/ITK,fedral/ITK,PlutoniumHeart/ITK,fedral/ITK,atsnyder/ITK,PlutoniumHeart/ITK,stnava/ITK,jcfr/ITK,zachary-williamson/ITK,blowekamp/ITK,PlutoniumHeart/ITK,spinicist/ITK,Kitware/ITK,fbudin69500/ITK,blowekamp/ITK,InsightSoftwareConsortium/ITK,BlueBrain/ITK,ajjl/ITK,msmolens/ITK,jcfr/ITK,thewtex/ITK,stnava/ITK,hjmjohnson/ITK,atsnyder/ITK,malaterre/ITK,PlutoniumHeart/ITK,stnava/ITK,vfonov/ITK,fedral/ITK,msmolens/ITK,stnava/ITK,BRAINSia/ITK,vfonov/ITK,LucHermitte/ITK,hjmjohnson/ITK,fbudin69500/ITK,stnava/ITK,hjmjohnson/ITK,fbudin69500/ITK,LucHermitte/ITK,jcfr/ITK,msmolens/ITK,jcfr/ITK,fbudin69500/ITK,InsightSoftwareConsortium/ITK,InsightSoftwareConsortium/ITK,zachary-williamson/ITK,LucasGandel/ITK,ajjl/ITK,fedral/ITK,msmolens/ITK,spinicist/ITK,PlutoniumHeart/ITK,stnava/ITK,Kitware/ITK,blowekamp/ITK,LucasGandel/ITK,spinicist/ITK,jmerkow/ITK,zachary-williamson/ITK,malaterre/ITK,fedral/ITK,InsightSoftwareConsortium/ITK,biotrump/ITK,spinicist/ITK,zachary-williamson/ITK,richardbeare/ITK,thewtex/ITK,spinicist/ITK,LucasGandel/ITK,malaterre/ITK,richardbeare/ITK,stnava/ITK,msmolens/ITK,LucasGandel/ITK,LucHermitte/ITK,BRAINSia/ITK,BlueBrain/ITK,Kitware/ITK,vfonov/ITK,fbudin69500/ITK,BRAINSia/ITK,BlueBrain/ITK,BRAINSia/ITK,fedral/ITK,msmolens/ITK,biotrump/ITK,spinicist/ITK,BlueBrain/ITK,atsnyder/ITK,InsightSoftwareConsortium/ITK,malaterre/ITK,thewtex/ITK,stnava/ITK,PlutoniumHeart/ITK,vfonov/ITK,LucasGandel/ITK,blowekamp/ITK,fbudin69500/ITK,vfonov/ITK,msmolens/ITK,atsnyder/ITK,BRAINSia/ITK,ajjl/ITK,zachary-williamson/ITK,richardbeare/ITK,LucHermitte/ITK,blowekamp/ITK,atsnyder/ITK,LucHermitte/ITK,zachary-williamson/ITK,jcfr/ITK,BlueBrain/ITK,thewtex/ITK,spinicist/ITK,biotrump/ITK,InsightSoftwareConsortium/ITK,BlueBrain/ITK,biotrump/ITK,richardbeare/ITK,LucasGandel/ITK,fedral/ITK,Kitware/ITK,atsnyder/ITK,jmerkow/ITK,hjmjohnson/ITK,biotrump/ITK