added cygwin specific stuff

cmake/EigenTesting.cmake

diff --git a/cmake/EigenTesting.cmake b/cmake/EigenTesting.cmake
index 0ea6ddd..d043f67 100644
--- a/cmake/EigenTesting.cmake
+++ b/cmake/EigenTesting.cmake
@@ -96,7 +96,11 @@
   endif(${ARGC} GREATER 2)
 
   if(WIN32)
-    add_test(${testname} "${targetname}")
+    if(CYGWIN)
+      add_test(${testname} "${Eigen_SOURCE_DIR}/test/runtest.sh" "${testname}")
+    else(CYGWIN)
+      add_test(${testname} "${targetname}")
+    endif(CYGWIN)
   else(WIN32)
     add_test(${testname} "${Eigen_SOURCE_DIR}/test/runtest.sh" "${testname}")
   endif(WIN32)