Clear out old Custom public leagues.

There are currently 26 public leagues listed under the existing league tabs. Only two of them is currently actually looking for members. The newest one other than those two is almost a year old and there are some other leagues there WAY older than that. 7 of them are over 6 years old and there are even older. There are leagues on there from 2015. The issue is, any new owner who may be interested in leaving the open leagues might see the list and A: be overwhelmed and B: think that no one is playing custom leagues when they see that there are that many leagues with that many spots that are that old.