Parsing folders, forbid added

All folders should be parsable (provided I can use Unicode without being
an idiot). Forbidden folders are indicated by a .STAYOUT file placed in
the directory.

README, ROADMAP, BUGS updated. ROADMAP priorities rethought on the basis
of what would be necessary and not just what would be fun.

Next up: a background process to update the forbidden directories every
so often, and a file parser/tagger.