Merge branch 'cmakelists-fftw3-hints' into 'master'

Add HINTS to find FFTW3

See merge request aroffringa/aoflagger!115

CMakeLists.txt

@@ -58,7 +58,7 @@ include_directories(${CASACORE_INCLUDE_DIRS})
 find_package(CFITSIO REQUIRED)
 include_directories(${CFITSIO_INCLUDE_DIR})
 
-find_path(FFTW3_INCLUDE_DIR NAMES fftw3.h)
+find_path(FFTW3_INCLUDE_DIR NAMES fftw3.h HINTS ENV FFTW3_INCLUDE)
 
 find_library(GSL_LIB NAMES gsl)
 find_library(GSL_CBLAS_LIB NAMES gslcblas)
@@ -79,7 +79,7 @@ include_directories(${PYTHON_INCLUDE_DIRS})
 find_package(Boost 1.56.0 REQUIRED COMPONENTS date_time filesystem system unit_test_framework)
 include_directories(${Boost_INCLUDE_DIR})
 
-find_library(FFTW3_LIB fftw3 REQUIRED)
+find_library(FFTW3_LIB fftw3 REQUIRED HINTS ENV FFTW3_LIB)
 include_directories(${FFTW3_INCLUDE_DIR})
 
 enable_language(Fortran OPTIONAL)