Findmypast US Link

I added the findmypast js link script to the links list.

Also, the event date search was a little broken.
findmypast receives either birth or death event
It wants the exact event year not 10 years off
The 10 years can be set in the offset variable

If this sounds like a good direction, I would love to make another pull request to handle persons without a birth year. So findmypast can be searched by the death year.