The only elements that do not have a discovery year are those that
have been known for about as long as we have historical records.
It is highly unlikely that we will discover a new element that will
not have a definite year of discovery, so NULL can be used to refer
to elements so old nobody knows who discovered it first.
The matching algorithm will work better when all names are normalized.
For instance, a search of "iorn" will not list "iron" in the first
three matches, but a search of "Iorn" will have "iron" as the first
match.