convert_song_el implemented with test data

Output from convert_song_el on first song in XML.
{3536: {'Album': 'KEXP Live Performances Podcast', 'Persistent ID':
'1B1440663BFF32B0', 'Location':
'file://localhost/Users/paulmccombs/Music/iTunes/iTunes%20Music/Podcasts
/KEXP%20Live%20Performances%20Podcast/KEXP%20Live%20Performance%20Podcas
t_%20The%20Gossip.mp3', 'File Folder Count': 4, 'Sort Artist':
'Gossip', 'Total Time': 1391544, 'Play Date UTC':
datetime.datetime(2006, 3, 7, 1, 21, 29), 'Sample Rate': 48000,
'Genre': 'Podcast', 'Bit Rate': 160, 'Podcast': True, 'Release Date':
datetime.datetime(2006, 2, 24, 21, 34), 'Kind': 'MPEG audio file',
'Name': 'KEXP Live Performance Podcast: The Gossip', 'Artist': 'The
Gossip', 'Date Added': datetime.datetime(2010, 5, 25, 5, 44, 8), 'Play
Date': 3224514089, 'Date Modified': datetime.datetime(2006, 3, 5, 20,
1, 25), 'Library Folder Count': 1, 'Year': 2006, 'Unplayed': True,
'Size': 27832978, 'Track Type': 'File'}}