Heuristically detect the encoding of a Western European text file.
Recognised encodings are US-ASCII, UTF-8, ISO-8859-15, WINDOWS-1252, and UNKNOWN.

Usage: detenc FILENAME (FILENAME ...)

Options:
  -o
    If the encoding is UNKNOWN, show the offset of the byte that didn't conform.
  -q
    Quiet: just give the encoding for each input file; don't print the filename.
  -v
    Print the version
  -h
    Show this help text.
