Canadian forest products company Resolute Forest Products Inc. has agreed to be bought by pulp manufacturer Domtar Corp. in a deal the companies valued at some $2.7 billion, including pension liabilities.   Resolute Forest shareholders will receive $20.50 a share for each Resolute Forest stock they own, marking a premium of about 64% to the stock's closing price on Tuesday. That would value Resolute Forest at roughly $1.6 billion. Resolute Forest shareholders will also receive a contingent value right that entitles them to a share of future softwood lumber duty deposit refunds ...