Update CGNS to 3.1.4-2 and add tests.

Closes #522.

cgns.rb

@@ -2,27 +2,33 @@
 
 class Cgns < Formula
   homepage 'http://cgns.sourceforge.net'
-  url 'http://downloads.sourceforge.net/project/cgns/cgnslib_3.1/cgnslib_3.1.3-4.tar.gz'
-  version '3.1.3.4'  # Release d of version a.b.c (we add the release to the version)
-  sha1 '148396af2b9f6b6b273561cf4e474e667adc7508'
+  url 'http://sourceforge.net/projects/cgns/files/cgnslib_3.1/cgnslib_3.1.4-2.tar.gz'
+  version '3.1.4.2'
+  sha1 '26c16ce5d01264aab208a588b636f1de6de4bb1f'
 
   depends_on :fortran
   depends_on 'cmake' => :build
   depends_on 'hdf5'
+  depends_on 'szip'
 
   def install
     args = std_cmake_args + [
       '-DENABLE_FORTRAN=YES',
       '-DENABLE_HDF5=YES',
-      '-DHDF5_NEED_ZIP=YES',
-      '-DCMAKE_SHARED_LINKER_FLAGS=-lhdf5'
+      '-DHDF5_NEED_SZIP=YES',
+      '-DHDF5_NEED_ZLIB=YES',
+      '-DCMAKE_SHARED_LINKER_FLAGS=-lhdf5',
+      '-DENABLE_TESTS=YES'
     ]
 
-    args << '-DENABLE64_BIT' if Hardware.is_64_bit? and MacOS.version >= :snow_leopard
+    args << '-DENABLE_64BIT=ON' if Hardware.is_64_bit? and MacOS.version >= :snow_leopard
 
     mkdir 'build' do
       system 'cmake', '..', *args
+      system 'make'
+      system 'ctest --output-on-failure'
       system 'make install'
     end
   end
+
 end