ETF providers rolled out a batch of funds while closing a raft of others this month. Here's an overview: New iShares Core ETFs Blackrock's iShares unit, the world's biggest ETF provider, launched four ETFs Monday in its new "Core" family that comes with rock-bottom annual management fees: 1. iShares Core MSCI Total International Stock ETF (IXUS) charges 0.16% in fees vs. 0.18% for Vanguard Total International Stock ETF (VXUS). Of 44 countries in