hdf5_ep

[svn-r6449] 
Purpose:
1.update windows release doc related to the addition of semi-automatic generated H5Tinit.c project and workspace files.
2. Make the doc more clear.
Description:
1. H5Tinit.c was manually maintained before and it might affect the users who wants to build and test from HDF5 snapshot release.
2. Make sure that we are supporting .Net only on XP and also emphasize to DLL users to the DLL critical section of the doc.

Solution:
1. Add a section for those users to semi-auto generate H5Tinit.c.
Platforms tested:
Doc files, no need to test.
Misc. update: