Start a Christmas sinking fund now, so next year’s holiday season is paid for before it begins   By Rachel Cruze   During the holidays, it’s so easy to get wrapped up in the spirit of giving — even after everyone’s been checked off the list. Just one more action figure for your nephew. One more mystery novel for your aunt. One more chew toy for the dog. It doesn’t feel like much in the moment ... until you look up and realize December cost way more than you planned. (If you e