fonts.cache-1 files (e.g. for grepping and validation of the mmap
codepath), as per James Cloos' request.
Remove done 'TODO' comment.
Updates for development release 2.3.90.
fc-cache once per cached architecture; add some documentation to the
FcCache structure.
Make fc-cache write out fonts.cache-2 files for directories with no fonts
(i.e. only subdirectories).