IBU and ABV calculators fixed

I finally had a chance to sit down and work on the calculators tonight without a baby, cat, or toddler wanting something. Sorry for the delay, it was a pretty simple fix, just needed to replace global variables since the host updated from PHP 4.1 to PHP 5.2. While reading around, I was struck with the temptation to get all AJAXy on them so they do live updating. Given how long the fix took, don’t expect anything soon.