Captcha added

I added Captcha to the comment posting page.  That’s the little thing that asks you to type in some obscured characters to prove you’re a human and not a robot script.  Since starting this blog there have been four real comments posted.  I have also had to delete several hundred comments that were nothing more than links to illegal drug sites, porn sites, or web pages that would load you up with the latest Windows virus or worm.  Or a combination.  None of them were ever visible, since I have to approve every post, but it was a pain in the ass.  Maybe this will help to stem the flow of spam.