(Reuters) - BlackRock and Credit Suisse reckon it is time to get back into equities after markets rallied this week following massive government and central bank stimulus packages to fight fallout from the coronavirus crisis.The $2 trillion U.S. fiscal stimulus has triggered big gains in global stocks, sending investors rushing to dust-off models from the 2008 crisis to gauge the right time to buy.World stocks have risen nearly 8% so far this week and were on track for their best weekly gain..