Refactorings.
* new/targets.jam
(main-target.apply-default-build): Call
'build-request.expand-no-defaults', not 'expand'. The motivation
is to have defaults added in one place: 'property-set.add-defaults'.
Also handle the case where default-build is empty.
(main-target.generate): Apply defaults here. The motivation is
that if we're using default build, default features should be
applied here as well, or else we'll get ambiguous alternatives.
(basic-target.generate): Do not add defaults.
[SVN r17755]
Vladimir Prus