Tree view of categories and subcategories

pkgsrc
        |- wip
        |       \- mk
        |- net
        |- audio
        |- mail
        |- wm
        |- www
        |- geography
        |- benchmarks
        |- devel
        |- news
        |- textproc
        |- math
        |- chat
        |- japanese
        |- graphics
        |- x11
        |- converters
        |- lang
        |- security
        |- databases
        |- ham
        |- perl5
        |- tk
        |- meta-pkgs
        |- sysutils
        |- python
        |- multimedia
        |- misc
        |- games
        |- cross
        |- fonts
        |- print
        |- comms
        |- time
        |- ruby
        |- gnome
        |- kde
        |- emulators
        |- editors
        |- linux
        |- biology
        |- pkgtools
        |- doc
        |- cad
        |- regress
        |- finance
        |-