[AGENT++] Leading '_' in defines and other places

[Andreas Vinsander]

Hi!
According to §17.4.3.1.2 of the ISO/IEC 14882:1998(E) C++ standard, 
leading underscore is reserved for the compiler's own use.
I have found several defines starting with leading underscore in the 
agent++/X source code. Just wanted to point it out to you... Things will 
probably work anyway, but any such literal (define, variable etc) with 
leading underscore might be a problem if it clashes with the compiler's 
internal usage.

/Andreas Vinsander