"Add stream to station" doesn't work

"Add stream to station" doesn't work.

'''Steps to reproduce:'''[[BR]]
 1. Open radio tab
 1. Add a station
 1. Right click on the station
 1. Click "Add stream to station"
 1. Enter URL and description
 1. Click OK

'''Result:'''[[BR]]
Stream is not added, this error appears in console:

{{{
Traceback (most recent call last):
  File "/usr/share/exaile/xl/db.py", line 172, in _execute
    cur.execute(query, args)
OperationalError: table radio_items has no column named url
INSERT INTO radio_items(radio, url, title, description) VALUES( ?, ?, ?, ?) (<xl.panels.CustomWrapper object at 0x88be02c>, 'http://209.247.146.98:8000', 'test', 'test')
}}}

This ticket was migrated from the old trac: re #784