add suggestion to ./ask
give up on filesystem.{h,cpp}

It turned out to be complicated, involving many assumptions regarding
the filesystem. Because Filesystem aimed to fix bugs regarding
--simulate, --simulate remains unstable. It will probably be deprecated.
add option: --ask-clean
deprecate --simulate, improve --ask-clean
add option --shallow-sort

This is useful if your filesystem looks something like:
Family Guy
└── S01
    ├── E01.avi
    ├── E01.srt
    ├── Family.Guy.S01E02.XviD.avi
    └── Family.Guy.S01E03.XviD.avi
Because then you can run:
Family Guy/S01$ vorg F* --shallow-output
update pretty print of Args
remove --simulate, add message before tests
add test for --shallow-output
simplify testsuite.cpp