Bug #245362 - Rewrite preserve-libs preservation code so that it always relies

Bug #245362 - Rewrite preserve-libs preservation code so that it always relies
on inode comparisons rather than string comparisons. Instead of injecting
libraries into $D before the files are merged, the preservation code now
executes after the files are merged but before the old version is unmerged.
After determining which libs to preserve, the CONTENTS are updated to include
those libs. The PreservedLibsRegistry.register() call is now done just after
the temporary vdb entry has been moved into place, guaranteeing that a valid
vdb entry is in place so that the unregistration code from bug #210501 is no
longer needed.

svn path=/main/trunk/; revision=11831