Add Makefile.client under mozilla/directory/c-sdk/config and call it
from mozilla/directory/Makefile (this "new" Makefile.client is
the same as the old mozilla/directory/c-sdk/Makefile that was
recently cvs removed).
Simplify the logic in mozilla/directory/build.mk and make sure the
command line tools are linked with the C++ compiler on all platforms
where necessary.
Recognize HP/UX 11.11 (treated the same as 11.00).
Replace an incorrect dependency on Makefile with a dependency on
Makefile.client inside the command line tools Makefile.client.