Raise mocha timeout to 3 seconds
Raise mocha timeout to 3 seconds

Timeout failure seen here:
https://travis-ci.org/CartoDB/Windshaft/builds/10977881

CartoDB/Windshaft,CartoDB/Windshaft,wsw0108/Windshaft,wsw0108/Windshaft,HydroLogic/Windshaft,manueltimita/Windshaft,HydroLogic/Windshaft,wsw0108/Windshaft,CartoDB/Windshaft,HydroLogic/Windshaft,manueltimita/Windshaft,manueltimita/Windshaft