Title in outline trees can be indirect. Allow outline->title to be nil.
Title in outline trees can be indirect. Allow outline->title to be nil.

darcs-hash:20080814210417-f546f-3de617e2ef379bc27f9c517f6947d8f8ddf6c692.gz

nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf,nqv/mupdf