jQuery KeyLimit Plugin for limiting key input on text forms.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
 
USAGE:
  Add 'klimit-*' to class attribute of input[type='text'] element
  which you want to limit key input. Just like this:

    <input type='text' name='number' class='klimit-digit' />

  Pre-defined 'klimit-*' classes are:
    - klimit-digit
    - klimit-hex
    - klimit-lower
    - klimit-upper
    - klimit-alpha
    - klimit-alnum
    - klimit-graph
    - klimit-mail

  You can also make your custom rule. For instance, if you want allow
  user to input only alphabets, numbers, dot(.) and underscore(_)
  as username, this will be done with:

    HTML
      <input type='type' name='username' id='username' />

    jQuery
      $('input#username').klimit([$.KLIMIT.ALNUM, '._']);

NOTE:
  The key code map to convert a character into key code (event.keyCode)
  is based on 101 US keyboard layout by default. If you want to alter
  some of key codes, assign key code map to jQuery.KLIMIT.KEY_CODE_MAP
  prior to jquery.klimit.js is loaded.
  This plugin also provides 'jquery.klimit.kb109.js' which defines
  key codes for 106/109 Japanese keyboard as an example. So if you
  work with 106/109 Japanese keyboard, you should implement your HTML
  as below:

    <script src='jquery.js'></script>
    <script src='jquery.klimit.kb109.js'></script>
    <script src='jquery.klimit.js'></script>