title: Bootstrap TableExport decimal issue
body: <p>I have a bootstrap table displaying employee data, including the payroll ID which have the given format: 1606.xxxx </p>
  
  <p>Here's what my table looks like :</p>
  
  <pre><code>&lt;table id="table_search"
      data-toggle="table"
      data-search="true"
      data-show-refresh="true"
      data-show-toggle="true"
      data-show-columns="true"
      data-show-export="true"
      data-minimum-count-columns="2"
      data-show-pagination-switch="true"
      data-pagination="true"
      data-page-list="[10, 25, 50, 100, ALL]"
      data-show-footer="false"
      data-export-data-type="all"
      data-export-types="['excel']"&gt;
      &lt;thead&gt;
          &lt;tr&gt;
              &lt;th data-field="id"&gt;ID&lt;/th&gt;
              &lt;th data-field="payroll_id" &gt;Payroll ID&lt;/th&gt;
              &lt;th data-field="nama_karyawan"&gt;Employee Name&lt;/th&gt;
              &lt;th data-field="level"&gt;Level&lt;/th&gt;
              &lt;th data-field="grade"&gt;Grade&lt;/th&gt;
              &lt;th data-field="title"&gt;Title&lt;/th&gt;
              &lt;th data-field="lokasi"&gt;Location&lt;/th&gt;
              &lt;th data-field="cost_sales"&gt;Cost Sales&lt;/th&gt;
              &lt;th data-field="dept"&gt;Department&lt;/th&gt;
              &lt;th data-field="div"&gt;Division&lt;/th&gt;
              &lt;th data-field="dir"&gt;Directorat&lt;/th&gt;
              &lt;th data-field="active_period"&gt;Active Period&lt;/th&gt;
          &lt;/tr&gt;
      &lt;/thead&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>The table displays it correctly, however when I export it into excel using <a href="http://issues.wenzhixin.net.cn/bootstrap-table/#extensions/export.html" rel="nofollow">TableExport</a> plugin it goes like this 
  <a href="http://i.stack.imgur.com/sogIs.png" rel="nofollow">exported results</a></p>
  
  <p>As you can see, somehow the plugin treats it as a number with decimal, which is exactly what I am avoiding. I've tried commenting the parseNumber function which might be the cause in the tableExport js file, however the results always comes out the same</p>
  
  <p>What am I doing wrong ? </p>
  
  <p><strong>PS:</strong> I don't want formatting after the file is exported, I want it to export the data as is.</p>