Modification of project handling and fixes.
* os.path.jam (basename, pwd, glob): New rules. Changed naming convention
for many other rules.
* project-root.jam: Use os.path everywhere.
* project.jam: Don't convert project paths to absolute paths. Use os.path.
* build-system.jam: Don't use absolute name when loading jamfile.
[SVN r13634]
Vladimir Prus