hdf5_ep

[svn-r8596] Purpose:
bug fix

Description:
Currently h5dump test on windows won't separate error form standard output; which shows at function error_message.
A #ifdef WIN32 macro at this file make stderr to be the same as stdout on windows.
Solution:
Separate standard error from standard output.

Platforms tested:
windows xp VS 6.0(by xuan bai), no needs to test on other platforms

Misc. update: