Add NDEBUG define for C/C++ compiles

[GoogleCodeExporter]

Some C/C++ users use assert() to catch errors whilst developing. Normally in 
production you compile with -DNDEBUG to turn off the assertion checking thus 
getting a slightly faster program and more importantly in this context, one 
which doesn't deliberately exit if an assert is triggered.

Please consider adding "-DNDEBUG" to the compiler switches for C and C++ code. 

Original issue reported on code.google.com by michael....@gmail.com on 21 Sep 2010 at 8:26