Log Message:
textproc/zet: update to 1.0.0

1.0.0 - 2023-04-18
Added
  - Add the --count-lines flag to show the number of times each line occurs in
    the input and the --count-files flag to show the number of files each line
    occurs in. The --count flag acts like --count-lines unless --count-files is
    active, in which case it acts like --count-files. The --count-none flag
    turns off counting, and can be used to override the other count flags.
    (In the usual POSIX convention, the last count flag given will override any
    previous count flag.)

Changed
  - Breaking: When - is used as a file argument, zet reads from standard input,
    not the file - in the current directory. (That file can be passed to zet
    as ./-)
  - When no file arguments are given, zet reads from standard input.
  - Breaking: Add the --files (alias --file) flag for the zet single and zet
    multiple commands. The zet single command now outputs lines that occur
    exactly once in the entire input. The zet single --file command reproduces
    the old behavior (output lines that occur in just one file, though possibly
    many times in that one file). Similarly, zet multiple --files reproduces
    the old behavior of requiring output lines to occur in more than one file,
    while zet multiple without the --files flag will output lines that occur
    more than once, even if in just one file.
  - Use clap 4's help format, but clap 3's colors. This is self-indulgent
    recreation of (part of) clap's help feature, because I like the clap 4's
    help format, but really miss the colored (rather than gray-scale) help.