field_mp3.inc causes fatal error for sites missing getid3.php

For users who checkout flexinode directly from CVS, they get all of the contributed field types automatically.

Because of the fact that field_mp3.inc does a require_once of getid3.php on EVERY page load, this immediately causes a fatal error for me when using flexinode.

I'd appreciate it if you could move the require_once for getid3 to flexinode_field_mp3_validate. As far as I can tell, this is really the only function that uses getid3, so this will prevent the fatal error (until the user actually attempts to use the MP3 field type) and also improve performance by only including code when it is needed.

A patch has been attached to accomplish this.