vchoi_fork

[svn-r11735] Purpose:
Cleanup.

Description:
Removed the home-made version of snprintf and vsnprintf since they
do not actually enforce the size parameter correctly and could corrupt
memory or as a security hole.
This block of code has been turned off since Aug 11, 2005 for all platforms
except Tflops.  No one has reported any problem since--sort of empirical
evidence that all platforms except Tflops support both functions.
Tflops has retired in September.  So, no need to keep this block of code.

Also, fixed the HDxxx macro to call the corresponding xxx function.

Platforms tested:
Tested in heping, both serial and parallel.