some cmake fixes for windows and GSL

test/CMakeLists.txt

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 366185e..e9a5eb1 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -2,6 +2,8 @@
 find_package(GSL)
 if(GSL_FOUND)
   add_definitions("-DHAS_GSL")
+else(GSL_FOUND)
+  set(GSL_LIBRARIES " ")
 endif(GSL_FOUND)
 
 set(SPARSE_LIBS "")
@@ -24,7 +26,10 @@
   message("CHOLMOD not found, this optional backend won't be tested")
 endif(CHOLMOD_FOUND)
 
-enable_language(Fortran OPTIONAL)
+if(NOT WIN32)
+  enable_language(Fortran OPTIONAL)
+endif(NOT WIN32)
+
 find_package(Umfpack)
 if(UMFPACK_FOUND)
   add_definitions("-DEIGEN_UMFPACK_SUPPORT")

test/main.h

diff --git a/test/main.h b/test/main.h
index 7363368..4c8b443 100644
--- a/test/main.h
+++ b/test/main.h
@@ -274,7 +274,7 @@
           std::cout << "Argument " << argv[i] << " conflicting with a former argument" << std::endl;
           return 1;
         }
-        seed = strtoul(argv[i]+1, 0, 10);
+        seed = int(strtoul(argv[i]+1, 0, 10));
         has_set_seed = true;
         bool ok = seed!=0;
         if(!ok)