Integrate ext/{libsfz,libzipxx,rezin}.

Integrate ext/libsfz da3b4ea.
Integrate ext/libzipxx 0a7b2bc.
Integrate ext/rezin 6ea8e24.
Merge branch 'integrate' into develop
Emplace into lists of strings.
Return unique_ptr<> objects.
Avoid shared_ptr<> when unique (or none) will do.
Keep queue elements owned.
Drop the last shared_ptr<>.
Swap "> >" for ">>".
Make CoreFoundation types moveable.
Improve initialization.
Merge branch 'cxx11' into develop