ENH: do not put system name into cygwin package

CMakeCPack.cmake

@@ -48,7 +48,15 @@ IF(EXISTS "${CMAKE_ROOT}/Modules/CPack.cmake")
     ENDIF(CMAKE_CL_64)
   ENDIF(${CPACK_SYSTEM_NAME} MATCHES Windows)
   IF(NOT DEFINED CPACK_PACKAGE_FILE_NAME)
-    SET(CPACK_PACKAGE_FILE_NAME "${CPACK_SOURCE_PACKAGE_FILE_NAME}-${CPACK_SYSTEM_NAME}")
+    # if the CPACK_PACKAGE_FILE_NAME is not defined by the cache
+    # default to source package - system, on cygwin system is not 
+    # needed
+    IF(CYGWIN)
+      SET(CPACK_PACKAGE_FILE_NAME "${CPACK_SOURCE_PACKAGE_FILE_NAME}")
+    ELSE(CYGWIN)
+      SET(CPACK_PACKAGE_FILE_NAME 
+        "${CPACK_SOURCE_PACKAGE_FILE_NAME}-${CPACK_SYSTEM_NAME}")
+    ENDIF(CYGWIN)
   ENDIF(NOT DEFINED CPACK_PACKAGE_FILE_NAME)
   SET(CPACK_PACKAGE_CONTACT "[email protected]")
   IF(UNIX)