More generator changes

From: Vladimir Prus (ghost_at_[hidden])
Date: 2005-06-09 05:50:21

Below is the copy of log for commit I've done today. Just for your 
information.

Modified Files:
generators.jam virtual-target.jam 
Log Message:
Further generators simplications.

1. If when generating something, we find more that one suitable generators,
run them and more then one return something, immediately report ambiguity.
Don't care if the produced targets are the same. This is better that
running several generators all the time, performance wise.

2. Remove the notion of 'intermediate' virtual-targets. IIRC, they were used
to prevent staging of RSP files, and we don't stage them anyway now.

-- 
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build V2: http://boost.org/boost-build2