.gitmodules:
Remove the submodules for example-clients and tools, as they are now
tracked in the separate project jack-example-tools
(https://github.com/jackaudio/jack-example-tools).

{Makefile.am,configure.ac}:
Remove all use of example-clients and tools and their respective
dependencies from the build system.

config/os/macosx/README:
Remove mentions of example-clients dependencies from OSX README.

doc/{Makefile.am,reference.doxygen.in}:
Remove all use of example-clients from the documentation generation.

man/*.0:
Remove all man pages now owned by jack-example-tools.