The wedding season is here. June is the second most popular month for saying, "I do!" June's 13% of annual ceremonies barely trails September's 14%, according to TheKnot.com. October, August and July are the three next most popular months for matrimony. One of the key challenges a couple-to-be faces is the decision about how far to merge finances. Failure to decide that issue to the satisfaction of both spouses can be costly. "More marriages fall