title: openerp form view don't display field data
body: <p>I found a problem with the <strong>stock</strong> module.
  I want to add some fields
  the data are well <strong>stored</strong> in the database but they are <strong>not displayed</strong> in the <em>view</em>!
  you find files module test</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;openerp&gt;
    &lt;data&gt;
  
          &lt;record id="view_picking_out_form_test" model="ir.ui.view"&gt;
          &lt;field name="name"&gt;stock.picking.out.form.test&lt;/field&gt;
          &lt;field name="type"&gt;form&lt;/field&gt;
          &lt;field name="model"&gt;stock.picking.out&lt;/field&gt;
          &lt;field name="inherit_id" ref="stock.view_picking_form"/&gt;
          &lt;field name="arch" type="xml"&gt;
              &lt;xpath expr="//field[@name='partner_id']" position="after"&gt;
                  &lt;field name="test" placeholder="e.g. [0-9][a-zA-Z]"/&gt;
              &lt;/xpath&gt;
          &lt;/field&gt;
          &lt;/record&gt;
    &lt;/data&gt;
  &lt;/openerp&gt;
  </code></pre>
  
  <p>test.py</p>
  
  <pre><code>from openerp.osv import fields, osv
  
  class stock_picking_out(osv.osv):
      _inherit = 'stock.picking.out'
      _columns = {
          'test': fields.char('Test Field', size=8, select=True, states={'done': [('readonly', True)]}, domain=[('type', '=', 'out')]),
      }
  </code></pre>