[Pipet Devel] PL changes

[valj01 at gel.usherb.ca]

I've made some modifications to the PL, which will require (very) minor
modifications to Piper.

First, 
     UIDocument::loadAllInfo();
has been replaced by 
     UINodeRepository::Scan();
in a cleanup of the XML layer. Also, by adding 
     IExtensions::detect();
at initialization, the PL looks for instruction set "extensions". For now, it
can detect AMD 3DNow! and Intel SSE so it can optimize some computations.

For now, it's only in CVS. I'll wait till things stabilize and I'll release
0.6.0 in around two weeks. This will be a major release, including things like
(limited) Win32 support and the ability to convert XML to plain C++ code that
can be compiled without Piper/Overflow. 

Stay tuned for more,

	Jean-Marc