USAGE: readability <source> [<source> ..] -<ARG> [-<ARG> ..]
  calculates the Flesch readability score for the textfiles <source>
  and counts different types of characters in <source>.
  Higher Flesch scores indicate material that is easier to read.
  There is no lower bound on the score. Use low scores to recognize bogus text.
  - for stdin as <source> is supported.
  The maximum linelength is 8112 characters.
Written to stdout is by default:
score <source>    ::= 206.835-(1.015*words/sentences)-(84.6*syllabes/words).
                  100.0 is easy to read. Below 30.0 is probably a bogus text.
sentences         Number of words ending on ":",";",".","?" or "!".
sentencelength    Average or totalcharacters for 0 sentences.
wordcount         Miniumlength is 1.
textlinecount     Number of non-empty lines. (Used if sentences is zero.)
syllabes          Defined by vowels "aeiouyAEIOUY".
wordcharacters    Number of characters in counted words.
blankcharacters   Number of spaces, form-feeds, horizontal or vertical tabs.
blankpercentage   100.0*blankchar/totalchar.
totalcharacters   Number of characters in <text-file> minus newlines,
                  carriage returns and trailing spaces.
apostrophes       Number of "'" (ASCII 39=0x27) characters.
escape            Number of Esc (ASCII 27=0x1b) characters.
extended          Number of ASCII 128-255 (0x80-0xff) characters.
punctuation       Number of "!(),.:;?[]{ }" characters.
special           Number of characters with accent:
                  "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõöùúûüýþÿ"
symbols           Number of characters:
             "!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¹º»¼½¾¿×Øß÷ø"
uppercase         Number of uppercase characters:
                  "A-Z" or "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖÙÚÛÜÝ"
capitalpairs      Number of uppercase letters followed
                  by an uppercase letter, hyphen or underscore.
numerical         Number of sequences of characters "0123456789-+.,"
                  containing at least one digit.
acronym           Number of sequences of at least two uppercase letters,
                  optionally interspersed with single or double lowercase
                  letters ("PvdA" is an acronym, "Hallo" not).
averagewordlength Average of all words, irrespective of length.
medianwordlength  Median of all words, irrespective of length.
ARG:
  -b[lock/]<n>    Flesch readability score per <n> wordcharacters.
                  Default: Flesch readability score per file.
  -b[lock/]1      Flesch readability score per textline.
  -b[lock/]-1     Flesch readability score per page i.e. up to line containing
                  a form feed (ASCII 12=0x0c). Empty pages are omitted.
  -e[cho]         write recognized words to stdout. Double spaces are skipped.
  -j[oin]         One line output for combined args -b, -e and -t.
                  Combining these 4 args facilitates sorting of the output.
  -n[onascii]     write lines containing non-usASCII characters to stdout.
  -r[ounded]      write only rounded <score> to stdout.
  -t[erse]        write only "score <score> <source>" to stdout.
                  It is prudent to filter the output with awk or grep
                  if the arg -t is not used.
SEE ALSO:
http://www.readabilityformulas.com/flesch-reading-ease-readability-formula.php
http://en.wikipedia.org/wiki/Flesch%E2%80%93Kincaid_readability_test
http://pigseye.revisor.leg.state.mn.us/stats/72C/09.htm
VERSION: Jun 24 2014

Copyright (C) 2011 by Harm J. Schoonhoven

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.