vchoi_fork

[svn-r14582] Purpose:
Fold all the updates made for v1.8.0 release to the main trunk.
Versions are from r14548 to r14556.  Changes are,

Updated section 4 for v1.8 release.
(May still check the v1.6 INSTALL to see if something can be adopted from
there.  But this is good for v1.8 release.)

Moved the section 2. "Warnings about compilers" to Appendix A; renumbered
section 3-7 to section 2-6 and fixed all section references.

Updated Website names from ncsa.uiuc.edu to hdfgroup.org or hdfgroup.uiuc.edu.

Updated section 1-3 and some of section 4.

Quick editorial review.
Convert tabs to spaces for consistent display and printing.
Verify and fix links and references.

Moved the following three paragraphs to the Appendix part since they have old
information that are not relevant most recent machines or compilers.
    "Large (>2GB) versus small (<2GB) file capability", 
    "Building and testing with Intel compilers"
    "Building and testing with PGI compilers"