By Mike Walters It’s official – sunshine makes you happy. Arsenal returned from their winter break refreshed, rejuvenated and as walking billboards for the adage that if you face the sun, the shadows will fall behind you. It remains to be seen whether a bunch of fives against Crystal Palace’s version of slip, slap, slop – slipping towards trouble, slapped in the chops by their own fans’ protests and sloppy at set pieces – will paper over the cracks and chronic shortage of a prolific goalscorer. But after three consecutive defeats, the Gunners needed to stop the haemorrhage and they found a tou…