Fix incorrectly swapped teritary if

It didn't really affect much, but in the logs, it was saying comments
were private messages and vice versa.
Add additional user information to YAML header

I'm getting real sick of all this spam.

Time to IP blacklist (plus gather some additional data for statistics
while I'm at it).

Privacy is an issue for many, so I will likely edit out the "sensitive"
information before actually publishing the valid comments to my blog.
Allow passing a 'debug' flag

This will print out the generated YAML data, but won't actually send it
or save it anywhere. Makes debugging a lot easier!

It's not a security vulnerability, since everythig that gets posted to
the debug page comes from data the user submitted (both in the form, and
through their HTTP header)

TODO: Print out more debug information, such as how the resulting email will look, etc.