coat calculator update

The advanced calculator has been updated! I fixed and rewrote the whole Rex/LaPerm/Hairless section, so everything should be good now. I've fiddled with it and I haven't seen problems with anything else, and I've checked through the silver and golden section again and determined that it is correct, so I'm going to call it finished and move on to the next project!

For my next genetics-related project I've added a poll to the sidebar. Please let me know what you'd like to see next!