Beginning of the 'make' rule.
* new/targets.jam: Check for duplicate 'basic-target::generate()' calls.
Use better logic to tell is source is another main target or file.
(project-target::has-main-target): New rule.
* new/project.jam (lookup): Fixes. (find-target): Implemented.
* new/make.jam: New file, defines the 'make' rule and associated target
class.
* new/build-system.jam: Import 'make'. Generate virtual targets and
actualize them.
* new/utility.jam: Added "MkDir" rule and actions.
* test/project_test3.py: New test.
[SVN r14249]
Vladimir Prus