Did Dish Network give CNN a helping hand this month? CNN posted a hefty 48% total viewer gain (602,000 viewers) in primetime for the month of January compared with January 2014, and a 72% primetime news demo gain (225,000). Nielsen’s January ratings period (December 29-January 25) will be remembered in cable news circles as the month in which Fox News Channel was blacked out of Dish customers' homes for nearly three weeks (the blackout started before the ratings period…