bdiff: document that bdiff_freehunks() accepts NULL
blocks() of cext/bdiff.c may pass NULL on OOM.
%include map-cmdline.default
[templates]
changeset = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{user}{ldate}{summary}\n'
changeset_verbose = '{cset}{branches}{bookmarks}{tags}{lphase}{parents}{user}{ldate}{lfiles}{lfile_copies_switch}{description}\n'