Merger Monday! Discovery Communications seals a $14.6 billion deal with Scripps Interactive. Jason Moser and Taylor Muckerman analyze Discovery’s opportunities for international growth. Snap’s lockup period expires, sending trading volume through the roof. But while Snap’s stock remains flat, the upcoming earnings report bears watching.  Plus, we dip into the Fool Mailbag to discuss Costco’s marketing push with....Groupon??