Fix #116: Prevent some browsers to persist the state of checkboxes.

From MDN page (https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/autocomplete):
Note: The `autocomplete` attribute also controls whether Firefox will — unlike other browsers — persist the dynamic disabled state and (if applicable) dynamic checkedness of an <input> element, <textarea> element, or entire <form> across page loads. The persistence feature is enabled by default. Setting the value of the `autocomplete` attribute to `off` disables this feature. This works even when the `autocomplete` attribute would normally not apply by virtue of its type. See bug 654072 (https://bugzilla.mozilla.org/show_bug.cgi?id=654072).

Author: mpryvkin

js/dataTables.checkboxes.js

@@ -1,12 +1,12 @@
-/*! Checkboxes 1.2.11
+/*! Checkboxes 1.2.12-dev
  *  Copyright (c) Gyrocode (www.gyrocode.com)
  *  License: MIT License
  */
 
 /**
  * @summary     Checkboxes
  * @description Checkboxes extension for jQuery DataTables
- * @version     1.2.11
+ * @version     1.2.12-dev
  * @file        dataTables.checkboxes.js
  * @author      Gyrocode (http://www.gyrocode.com/projects/jquery-datatables-checkboxes/)
  * @contact     http://www.gyrocode.com/contacts
@@ -150,7 +150,7 @@
 
                if(ctx.aoColumns[i].mRender === null){
                   colOptions['render'] = function(){
-                     return '<input type="checkbox" class="dt-checkboxes">';
+                     return '<input type="checkbox" class="dt-checkboxes" autocomplete="off">';
                   };
                }
 
@@ -994,7 +994,7 @@
       * @type {mixed}
       * @default `<input type="checkbox">`
       */
-      selectAllRender: '<input type="checkbox">'
+      selectAllRender: '<input type="checkbox" autocomplete="off">'
    };