Almost ready?

Over the last couple of days, I've made some good progress on the next release of the Compendium.

In addition to fixing a couple of bugs with the previous iteration, I've tidied up the validation on the new XP and Cost filters to avoid a problem with the Wizards.com API.

I'll be putting the current version - 0.4.8 - through its paces over the next couple of days, and hopefully should have a date in mind for the next release by the end of the weekend, pending any further issues.