Jason,
somme of our customers have 'interesting' C++ coding rules, they'd like to have 
the compiler enforced.  They want to disable:

1) namespace definitions
2) template declarations
3) multiple inheritance
4) virtual inheritance

But they want to use the STL.  This patch implements 4 new flags, intended to be 
use in the -fno-FOO form.  They're only active outside of system header files.

1) -fno-namespaces disables namespace definitions, but not using directives or 
qualified names.

2) -fno-templates disables primary template declarations, but not template 
instantiations or specializations (partial or otherwise).

3) -fno-multiple-inheritance disables direct multiple inheritance, but not 
indirect multiple inheritance

4) -fno-virtual-inheritance disables direct virtual inheritance, but not 
indirect virtual inheritance.

Thus you can't use any of these features directly, but one can use the STL and 
have it behave as intended.

WDYT?

nathan