Added a captcha question/answer to registering on the wiki.
Here are the questions/answers (not like they were self-evident).
question "What planet are you on?", answer "Earth"
question "What is the answer to Life, the Universe, and Everything?", answer "42"
question "What is the name of the planet Mars?", answer "Mars"
question "What color is blue?", answer "Blue"
Answers are without quotes.