Node.cpp: let plist_t operations free _node when in a container.
Node.cpp: let plist_t operations free _node when in a container.

Fixes libimobiledevice/libplist#50.

libimobiledevice/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,Tatsh/libplist,libimobiledevice/libplist,libimobiledevice-win32/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist,Tatsh/libplist