Write support for:
  - ftp
  - floppy
  - dav
  - ugz
  - ubz2
  - utar

Flush file caches

uzip - symlinks
ucpio - builtin
option for uzip, not to convert filenames to lowercase

automatic handler detection based on extension AND content

Redir should support operations:
  - open(..., O_CREAT, ...)
  - creat
  - truncate
  - utime
  - chmod
  - chown
  - lchown
  - unlink
  - rmdir
  - mkdir
  - mknod
  - symlink
  - rename
  - link

Redir can't support following symlinks to virtual files. Find better solution

Avfscoda:
  - Clean soloution to file access permissions
  - Faster random access to files (at least streaming access)

Preload:
  - remember cwd after exec
  - add missing operations
