Rewiring stderr to a logger is now idempotent
Rewiring stderr to a logger is now idempotent

There was a bug where instantiating Logging twice would rewire stderr to a logger that logs to another logger.

cberner/airlift,johngmyers/airlift,johngmyers/airlift,gwittel/platform,haozhun/airlift,johngmyers/platform-rack,mono-plane/airlift,johngmyers/airlift,daququ/airlift,johngmyers/platform-rack,haozhun/airlift,haozhun/airlift,proofpoint/platform,airlift/airlift,dain/airlift,haozhun/airlift,erichwang/airlift,airlift/airlift,electrum/airlift,zhenyuy-fb/airlift,cberner/airlift,airlift/airlift,johngmyers/platform-rack,electrum/airlift,erichwang/airlift,johngmyers/platform,martint/airlift,mono-plane/airlift,daququ/airlift,airlift/airlift-rack,electrum/airlift,mono-plane/airlift,airlift/airlift,proofpoint/platform,daququ/airlift,johngmyers/platform,dain/airlift,dain/airlift,gwittel/platform,johngmyers/airlift,johngmyers/platform-rack,cberner/airlift,zhenyuy-fb/airlift,electrum/airlift,gwittel/platform,airlift/airlift-rack,johngmyers/platform-rack,erichwang/airlift,dain/airlift,daququ/airlift,johngmyers/platform-rack,zhenyuy-fb/airlift,proofpoint/platform,zhenyuy-fb/airlift,johngmyers/platform,martint/airlift,mono-plane/airlift,martint/airlift,cberner/airlift