add dependency on libuuid
add UUID to port type
update branches for uuid work
first pass at working UUID-based clients and ports. many JACK clients work correctly without recompilation
fix screw up caused by attempting to uuid_parse() a null string UUID in jack client arguments
fix display of new client UUID in verbose mode, and add errno if initial client read(2) fails
miscellaneous fixes to prepare the way for usable metadata

* move port UUID initialization into engine so that it is actually shared across clients
* export jack_server_dir() within libjack
update submodules
add jack_client_t* to metadata calls that need to contact the server to initiate a property change callback
update submodules
update submodules
set up property change notification structures and calls
add property change notifications
update submodules
differentiate between property changed/created in PropertyChange notification (by testing for existence first)
implement jack_get_all_properties() and cleanup a few other implementation details
update submodules
add new man page for jack_property(1)
fix typos
add -U option to jack_lsp man page